African Violets How to grow and bloom at home
Table of Contents Introduction to African Violets The Origin of African Violets
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Caring for African Violets Growing from Seed
5 5 5 6 6 6
Mixtures for Seeding Containers for Sowing Preparing for Seeds Seedlings
Other Methods Leaf Cuttings Rooting in Water Stem Cuttings Potting the Young Plants Division
How to Care for Soil Temperature and Humidity Fertilizers New Plants Old Plants Watering Overhead Watering Subirrigation
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9 9 10 11 11 13 15 16 17 18 19 20 21 21
Diagnosis of Troubles Gasses Leaf Bleaching Ring Spot Over Fertilization Leaf Stalk Rot Bud Drop Stunt Stem or Crown Rot Mildew
Pests Nematodes
25 25 25 25 25 26 26 26 26 27
Mites Mealybugs Thrips Aphids or Plant Lice Springtails
27 27 27 28 28 28 28
African Violet Groups
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Introduction to African Violets The African violet has become extremely popular, because it can be grown satisfactorily in the average home by almost anyone who takes a little care in handling and tries to understand the simple principles of the care involved. The variety of coloring in the flowers, the beauty of the foliage, the almost constant bloom from the youngest stage on, the continuance of flowering throughout the year, and the adaptability of the plant to the trying conditions of the average home have made it a universal favorite. Its ease of propagation has appealed to old and young alike, and its variety of form, shape, and color has given many a busy man or woman a green thumb; and incidentally, has changed many a home from a stiff, drab affair into an intimate, living picture.
The Origin of African Violets The African violet is a native of East Africa; and, although actually is not related to our native violets, gets it name from a certain resemblance to them. The generic name given to it, when it was discovered in the summer of 1882, was Saintpau-
lia, after Governor Walter von St. Paul of Usambara in East Africa, who sent seeds to a German botanist, Wendland. He was the one who named it the German equivalent for “African violet� and that name has stayed with it. If you are interested in the full name of this original, it is Saintpaulia ionantha(which means in Greek: flowers like a violet). In Africa, where these plants originated, they grow in partial shade of various densities, depending on the kinds and localities. Some grow in very low elevations and some in high (up to 3,000 feet) and usually in soil containing lots of humus. These native conditions give us the clue to their best culture, which will be discussed later.
Caring for African violets Let us The African start violet at thehas beginning become extremely of things popular, and see how because African it can violets be can grown be startsatisfactorily ed from in scratch the average in thehome average by almost home. anyone You can who do sotakes from aseed, littlebycare leaf in or stem handling andand cuttings tries separation to understand or division the simple of the principles plant into of several the care parts. involved. The variety of coloring in the flowers, the beauty Growing Seed. of the foliage,From the almost constant bloom Under home the from thenormal youngest stage conditions on, the continplants will not set enough seed to bother uance of flowering throughout the year, with andadaptability when they of do,the it would bethe at and the plant to the expense of future blooming and gentrying conditions of the average home eral plant. Hence, those havevitality made of it the a universal favorite. Its who are interested in starting the African ease of propagation has appealed to old violets fromalike, seed and should buy this from and young its variety of form, commercial growers who make a speshape, and color has given many a busy cialty it. Theaseeds very and fine inciand man orofwoman greenare thumb; almost dust-like, so that they have to dentally, has changed many a home from be handled quite into differently from such a stiff, drab affair an intimate, seeds as zinnias, which you plant out of living picture. doors in the spring of the year.
lia, after the mixture Governorshould Walterbevon sterilized St. Paul by of Usambara heat: steam, in East hot Africa, water whoorsent hotseeds air. to aSuch German a mixture botanist, is composed Wendland.of He eiwas ther the one sandwho or named soil. (Manufactured it the German equivalent ingredients for “African such as Vermiculite violet” and that and name Perlite has stayed are sterile. with it. Peat If youmoss are interhas estedbeen in the known full name to contain of this disease original,orit is Saintpaulia ganisms, soionantha(which it is best to sterilize meansthe in Greek: complete flowersmixture like a violet). after preparation.) The best method at home is to place In Africa, soil or sand wherein these a pot or plants dish originatin a preed, they heated grow 200° in partial F ovenshade and heat of various it for densities, a period depending of one hour. on the (2) The kindsmediand localities. um used Some should growdrain in very well. low(3)elevaThe tionsseeds and some should in high not (up be covered to 3,000 with feet) and any usually mixture, in soilbecause containing they lots are so of fine humus.that These thenative youngconditions seedlings give would us not the cluebreak to their through best culture, a cover.which (4) Moisture will be discussed in a mixture later. should be adequate. (5) A minimum temperature of How Increase Violets 65° to F should be maintained.
All of violet mixtures are suggested for Thekinds African is a native of East Afseed sowing and most of them satrica; and, although actually is notare related isfactory. The important facts to to our native violets, gets it name from a remember are: certain resemblance to them. The generic (1) the mixture sterile, name given to it, whenshould it was be discovered thatsummer is, free from disease in the of 1882, wasorganisms Saintpauand insect pests. To accomplish this
All of contrivances have used andkinds see how African violets canbeen be startfor holding the mixture sowing.home. Some ed from scratch in theofaverage types of containers will need sterilizaYou can do so from seed, by leaf or stem tion; with others, a thorough washing is cuttings and separation or division of the sufficient. Clay pots, unless new, are noplant into several parts. torious for harboring disease organisms. Some growers used Mason jars filled
The Origin of African MixturesViolets for Seeding.
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at Home Containers forbeginning Sowing. Let us start at the of things
with a sowing mixture and laid horizontally. Seed is sown with a spoon, scattering it as evenly as possible. The jar cover should then be screwed on without a rubber ring. Some growers use glass casseroles, the bottom of which is covered with charcoal for better drainage with the seeds sown lightly over the surface of the growing medium. The entire dish is then covered with the casserole top. Crushed stone, gravel, or broken clay pots can also be used for drainage. These materials require sterilization. (1) use a shallow, sterilized clay pot or seed pan. (2) Fill the bottom with an inch of charcoal.(3) Cover the charcoal with 2 inches of thoroughly wet peat moss. (4) Cover with ½ inch of sand which you have baked in the oven as suggested or substitute Vermiculite for the sand. (5) Wet the entire mass thoroughly. However, in containers without drainage holes, do not add excess water when wetting the medium. (6) Sow seeds on top of the upper layer and place nothing over sown seeds. (7) Cover the pot or pan with a piece of glass. A clean sheet of polyethylene is also excellent for covering seed
flats, since water vapor cannot pass through, but some exchange of oxygen and carbon dioxide will occur. (8) Set seed container in a warm (7075° F) room, not in full sunlight. glass. A clean sheet of polyethylene is also excellent for covering seed flats, since water vapor cannot pass through, but some exchange of oxygen and carbon dioxide will occur. (8) Set seed container in a warm (7075° F) room, not in full sunlight.
Preparing for Seeds. We think that the simplest method and the most satisfactory is as follows: nothing over sown seeds.
Seedlings.
Small green seedlings will begin to appear in about two weeks. During this period you will not have to do any watering, because the peat moss was wet thoroughly and the sand on top has thus been kept moist. Water for this development and immediately bring the container to a lighter place: about the darkness of an average room, and lift the cover to provide air for the seedlings.
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Air should be given gradually; only the thickness of a toothpick under one side of the glass is necessary the first day. Then gradually allow more until within a few days the cover can be removed altogether. Now is the time to check for surface drying. Moisture will have to be provided and may be supplied by using a small sprinkling can with little pressure. If necessary, water may also be poured on with a spoon. Subirrigation by standing the container in a pan of water until moisture reaches the surface of the soil is excellent for young seedlings. The important point is not to injure the tender seedlings by dislodging them or covering them with soil by forcible watering. Once the second set of leaves appears, a weak fertilizer solution should be used when watering. Generally speaking, fertilizer is most important in situations where an inert medium like Vermiculite has been used. Media containing soil should not require fertilizer under normal conditions. If fertilizer is used,
a good liquid plant food serves the purpose. When seedlings get to a height of about one-half inch with 3 to 4 leaves (about 5 to 6 weeks after germination), transplant the individual seedlings to a 2½inch pot, using a soil mixture of one part soil one, part sand and one part peat moss. Potting mixture for young seedlings should be sterilized to avoid soilborne diseases. When lifting the seedling, take it out with a pickle fork, and since the roots were in peat, some peat will cling to them. The seedlings can also be pricked from the seedling container with wooden tweezers. In either of these ways you do not break off too many roots and the young plants will start off in a hurry. Water thoroughly after firming the soil about the roots of the seedling, set the young plants in a light room without direct sunlight on them. Avoid too severe packing of the soil or drainage and aeration problems may develop. It will take from 6 to 9 months to produce flowers on such plants.
Other Methods Leaf Cuttings.
(1) Cuttings taken during the spring usually produce flowering plants more quickly than those taken during the summer or winter. Leaves selected for propagation should be mature, but not old, for best results. (2) Remove leaves from the plant with a sharp jerk so that no stub is left to rot. (3) Cut the base of the stalk with a sharp knife, leaving a length of ½ to ¾ inches from the base of the leaf blade. Longer petioles simply prolong the time when young plants will develop. (4) The rooting medium could be sharp, clean, sterilized sand or half sand and half peat moss. Vermiculite or perlite (concrete grade aggregate) which is available from building supply dealers or garden supply centers may also be used. If basal rot does occur, drainage may be poor, too much water is being applied or the propagating medium is not sterile and the petiole cuttings are contaminated by disease. (5) This potting material can be placed
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in a 6-inch pot in a room such as the kitchen where humidity is higher than in other rooms. (6) An old aquarium is excellent because the glass sides are high enough so that moisture is retained in and around the cuttings. Drainage material such as crushed stone, gravel or charcoal should be placed in the bottom. Fill it with 2 to 3 inchees of rooting medium. (7) The cutting itself is inserted into the rooting medium by making a hole wit ha pencil or dribble (tapered stick) to a depth of about 1½ inches, sticking the cutting into this hole on a diagonal and pressing the medium carefully about the base of the cutting. Properly prepared medium even permits insertion without making a hole. (8) The next step, after all the cuttings are in, is to water them in with warm water carefully (100° F to 105° F). (9) The container should be kept away from direct sunlight. (10) Keep the humidity up by a daily light spray of water. An easy way to maintain high humidity is to put a plastic bag over the container of cuttings. In all cases be sure excess water does not accu-
mulate. (11) If possible, do not allow the temperature to go below 65-70° in the room where this rooting is taking place. The ease with which African violets root by leaf cuttings has made a great variation of methods possible. We have seen broken leaves drop to the benches in a greenhouse and root and develop without any attention. We have seen leaves drop to the ground from plants in the humid seasons in Florida and root quickly. However, to avoid confusion, the surest method is as follows: Under such conditions rooting will take place and new plants will form at the base of the cutting in about 5 weeks to 4 months, depending on the variety. If the base of the stem is split before insertion, more young plants will develop than if a single slanting basal cut is made.
Rooting in Water. The same kind of cutting can be rooted in water by using a colored glass or a bottle. In clear glass rooting takes place more slowly and green scum (algae) develops more rapidly. Clear glass can be wrapped in aluminum foil to exclude light. Put 1 inch of charcoal in the bot-
tom of the container. Cover the glass with wax paper, cut slits and insert cuttings as indicated. One or two additional openings in the cover to permit entrance of oxygen is advisable. The glass should be filled deeply enough to cover the bases of the stems to a depth of ¾ to 1 inch. Keep the container in a warm room, away from drafts and direct sunlight. As the water evaporates, add more. One particular precaution must be observed: in case of cuttings set in some rooting medium, it is well to wait until young plants have begun to develop before removal from the medium. When started in water, as soon as the roots are ½ to ¾ of an inch long, the cuttings should be removed and potted. You will read later about the need of special water for such purposes. In most cases it is not necessary, but to be on the safe side you could use distilled water, which you can buy from your gas station or drug store. It should be pointed out, however, that traces of metal irons may be present in distilled water which may be extremely toxic to rooting because of lack of antagonism from other irons normally present in tap water.
My illustration on stem cuttings 10
Stem Cuttings. Another phase of propagation, which may be practiced if plants are wanted more quickly than those from cuttings, is the use of stems with several leaves. These may be cut off from the parent plat and potted without roots in the soil suggested above. They will root quickly, provided they are kept out of drafts. In fact, these plants could be covered by a large glass or bottle to retain humidity. Another method is to set such plants as cuttings in an old aquarium as suggested for leaf cuttings, but in this case, cover the top with glass or cloth to keep moisture in. After rooting, such as plants can be potted. Later, the cutting leaf of each plant can be removed with a sharp, clean knife and rerooted to make another plant.
Potting the Young Plants.
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African violets naturally grow in welldrained soils with a high content of humus, so we use soil mixtures which approximate natural conditions. Any number of combinations can be suggested, but a good, safe one is composed of one part soil, one part sand, one part peat moss or leaf mold. Commercially-prepared African violet soil is sold in variety stores and garden centers everywhere. The soil provides the nutrition; the san, the drainage and air; the humus helps hold moisture. If you use sphagnum peat moss, you will find it retains not only water, but also holds nutrients and improves aeration. The cutting from the water glass which has
no young plants developing should be potted high-the roots barely covered by the soil mixture. The pot itself could be a 2 ½-inch clay pot, a plastic or painted pot of the same size. The latter two will hold more moisture because evaporation is reduced. Care should be taken not to over water or underwater because of this property. The bottom of the pot should be covered with charcoal, gravel, crushed stone or broken clay pots for drainage and the soil firmed after potting by a thorough watering. In the case of the cutting which was been rooted in a solid medium, several young plants will develop at the base. You can either separate these carefully and pot each one separately or pot the entire leaf with the young plants together. If you separate the plants, you will have many more eventually, so it really pays to do that. The young plants may be broken apart gently if special care is given not to tear the roots off. Dust the severed parts with a good fungicide. There is no particular advantage in having a multicrowned plant to start with except that it looks larger at the beginning. As the plants begin to develop and touch the rims of the pots, it is an excellent idea to cover the rims with any wax, scotch tape or aluminum foil. This keeps the leaves that come in contact with the rim of the pot from rotting due to fertilizer salts which rise through the porous pot and form a crust on top, as a result of water from the bottom. Occasional
watering on the surface to cause some leaching will help reduce this problem. If painted, metal or plastic pots are used, such precautions are unnecessary.
My illustration on potting plants
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Division. Propagation by cuttings at best is a slow method, taking from 4 to 12 months before a sizeable flowering plant is developed. By dividing a plant, which has several “crownsâ€? (a growing point surrounded by a cluster of leaves) into separate plants, large flowering plants are secured more quickly. Usually after blooming profusely, the violet has a partial period of rest and that is the time to knock the plant out of its pot and separate carefully the several crowns which may be developed. Since plants bought from a commercial grower are usually multi-crowned, you will probably want to divide them after you have had them in your home a few weeks and the flowering has decreased. The actual process consists of removal of the plant from its pot by knocking the pot against a solid object to loosen the ball of soil from the container. This is facilitated if the soil is only slightly moist at the time of operation. Some soil may be shaken off gently so that none of the root system is destroyed and the crowns cut apart with a sharp sterile knife or broken apart gently, making sure that each contains its share of roots. Dust the cuts with a fungicide. Then the new plants should be potted, each one to a pot, the size depending upon the size of the crown. They may be placed back into 2 ½ or 3-inch pots. It is best to shift plants gradually to larger pots after roots begin to develop on the outside of the soil ball. Too much volume of soil may
tend at first to keep the roots too wet and cause them to rot from lack of air in the soil. It is important to remember that the crown of the plant should not be buried. Again, charcoal drainage in the bottom of the pot is recommended, using the same soil mixture as suggested fro the potting of cuttings. In potting the soil should be sifted carefully about the roots and pressed gently to compact it, so that it comes in close contact with the roots. In all cases at least ½ inch of space should be left between the soil and the top of the pot to allow for water. Immediate and thorough watering is essential. The pots themselves in all cases should be clean. They should be scrubbed with hot water and soap if they have been used before to remove all dirt and salts. Soaking used pots in boiling water 15 to 20 minutes helps to remove salts and disease spores and makes the cleaning task easier. In addition they should be sterilized for 30 minutes or more at 180°F., preferably in an oven. New clay pots do not need such treatment, but should be soaked in water for at least 15 minutes before being used so that they become saturated; otherwise, they will withdraw water from the soil ball and may cause drying out of the roots. Plastic pots or other non-porous pots should be thoroughly cleansed on the inside if they have been used before. Do not steam or sterilize plastic pots, however, because they melt at high temperature.
How to Care for Soil African violets have rather fine roots and hence grow best in soils which are well granulated, well drained and contain adequate amounts of air. Although it is true that these plants apparently grow in a wide variety of soils, the above conditions must be observed. Actually, the many different kinds of mixtures advocated sum up to a soil which is composed of about half and half of minerals and humus. The average loam mixed with sand and such humus as leaf mold, peat moss, etc., will grow good violets. The usual proportions are 1 part loam, 1 part sand and 2 parts humus. The latter may contain any one of the above-mentioned materials or a combination of two or three. In all cases, however, this organic matter (humus) portion should not be well decomposed. For instance, if leaf mold is used it should consist of the leaves only partially rotted down. For the same reason German or Canadian sphagnum peat moss is more satisfactory than the fine mucks which are frequently substituted. In many places it is difficult to obtain and mix the proper ingredients. In such cases the local florist can prepare the soil 15
for you or you can buy African violet soil already packaged in variety and garden stores. The soil mixtures you use should not be highly acid. Slightly acid or neutral soils are best (pH 5.8-6.8). Because of various soil pests and diseases, it is best to sterilize the mixture by heat, either through use of steam or direct heat. The notion that heat kills most of the beneficial organisms in the soil is not warranted, since many of these organisms exist in the air and the soils become reinoculated with them quickly. Furthermore, the apparent discrepancy between the amount of light in the basement and the suggestion made for the best growth (1000ft. candles) lies in the fact that the 1000ft. candles recommended are not constant, actually fluctuating from 100 to 1000ft. candles, whereas the 300 ft. candles in the basement were constant. Such a test can be duplicated in any home where the basement is warm and where humidity can be raised by sprinkling the floor. In the living room, particularly during winter, inadequate light may be increased by using a standard cool white light as suggested above as a supplement
to daylight. Such lamps used for a period of 10-12 hours per day could really make for perfection, provided that temperatures, humidity and other necessities are taken care of. These are discussed in the following pages.
Temperature and Humidity These two factors go hand in hand in promoting proper growth of violets. African violets come from tropical countries and naturally grow best when similar growing conditions are provided. The average home usually provides dry and hot growing conditions, so some simple modifications are essential. The best temperatures for African violets are 65700 at night with day temperatures the same or 10 degrees higher. Cool rooms where there is a little heat, especially at night, are not satisfactory. Likewise a window sill is often not right in winter because of the closeness of the plant to the cold glass unless paper, cardboard or some other material is placed between the plants and the glass each night. It is very difficult to maintain such high humidities in the average home, no matter wheat type of heating is used, unless
the homes are air conditioned. Ordinary humidity in the home, generally speaking, is all right for average growth except in arid sections of the country. In areas where normal high humidity is available outdoors, as for example, in and about San Francisco, or at certain periods of the year in Louisiana or Mississippi, there is no problem. In other areas some provisions should be made in the home to keep the moisture high in the vicinity of the plants themselves. In kitchens where steam from cooking permeates the air, we approach ideal conditions. Elsewhere, the use of plans of wet sand or pebbles in water with a large evaporating surface helps. To make sure that the most ideal temperatures and humidity that your home can provide are maintained, avoid drafts and sharp changes from hot to cold or the reverse. Consideration could be given to the installation of a humidifier that will supply adequate humidity up to somewhere near normal for your plants’ sake and your health’s sake. The use of the will amaze you. In the average hone it is easily possible to put 7 to 8 gallons of water 16
into the air every 24 hours. You will feel better and so will your plaints. Before using the soil mixtures mentioned previously, it would be well to have the soil tested by your experiment station, unless you buy already-prepared soil. The reason for this is that the basic soil that you use and to which you add sand and peat moss or leaf mold may or may not contain enough plant food to carry your paint for nay length of time. If, however your soil is deficient, lime and superphosphate can be added before potting, and nitrogen and potash in liquid form, applied after planting, based on the needs of the plant.
Fertilizers In a recent experiment on fertilizing African violets, 3 lbs. of 20-20-20 commercial fertilizers per 100 gallons of water applied every two weeks resulted in the best plaints. For heaviest flowering, however, a fertilizer with less nitrogen is best. Fertilizers may be added In dry form and watered in or in liquid form. Liquid form is safer and more effective if
applied about once a month at half the strengths usually recommended. Actually, if you want to do a real job of keeping the fertilizer levels right in the soil, the following recommendations should be followed: nitrates, 10-25 ppm; phosphorus, 5 ppm; potassium, 20 ppm; calcium, 150 ppm. These are based on the Spurway system of soil testing. It at all possible, have your soil testing. If at all possible, have your soil tested and interpreted by soil testing personnel for the best accuracy. A simple way to feed your African violets is to use any liquid plant food as directed, if you are careful to keep the fertilizer off the leaves. Before applying, be sure that the soil in the pot is moist. Do not worry whether the fertilizers you buy contain hormones or vitamins. If they do, you are paying them for no good reason. Like other miracles, they have their places, but not in your African violet soil.
African violets are easiest to pot when they are small and the leaves do not extend over the edge of the pot. There is no special season when potting may be done. Rooted cuttings should be potted when new growths have developed at the base of the leaf stalk. Older plants are best shifted to a larger pot after flowering has decreased and when examination of the ball of soil indicates that it is filled with roots. Under such conditions a reporting job is in order to prevent any check in growth. As indicated previously, the pots used should be thoroughly cleaned on the inside and preferably sterilized by boiling. New pots should be soaked in water, while non-porous pots need only a thorough cleaning on the inside.
New Plants In potting small plants bare root–that is, without any ball of soil, put a little charcoal or other coarse drainage material in the bottom, cover that with soil; then, holding the plant in one hand so than
the one the plant was growing in. For example, a plant out of a 2 ½ inch pot could be shifted or repotted into a 4-inch pot. In such a case the soil ball should have any green cum (algae) removed from the top and the edges crumbled off lightly. The soil should be moderately moist. If the soil is too wet, the ball will stick to the pot; if too dry, it will crumble away from the roots. Test the soil for consistency by squeezing some in your hand and then dropping it. If the soil forms a ball when squeezed, but shatters when dropped, it is just right. that it is about ½ inch below the rim of the pot, pour the soil in around the roots with the other hand. Finally, tamp the pot gently and firm the soil with your hands so that is makes good contact with the roots. Be sure that when you are finished, ½ inch space is left below the rim of the pot for water. Then water thoroughly. If you plant to grow your plants by watering them from below, no charcoal or any other drainage material should be placed in the bottom of the pot.
Old Plants Shifting of older plants consists of taking pot somewhat larger than the one the plant was growing in. For example, a plant out of a 2 ½ inch pot could be shifted or repotted into a 4-inch pot. In such a case the soil ball should have any green cum (algae) removed from the top and the edges crumbled off lightly. The soil should be moderately moist. If the soil is too wet, the ball will stick to the pot; if too dry, it will crumble away from the roots. Test the soil for consistency by squeezing some in your hand and then dropping it. If the soil forms a ball when squeezed, but shatters when dropped, it is just right.
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To remove the old plant from its pot, turn it upside down while holding the plant with two fingers, placed on top of the soil and tap the rim of the pot gently against a solid object which will loosen the soil away from pot.. Drainage, such as charcoal, should be placed in the bottoms to a depth of ½ to 3.4 inch and covered with soil so that when the ball is set on top of it, it will be about ½ to ¾ inch below the rim of the new pot. Then fresh soil should be poured around the old ball and tamped
around it with a label or a stick to make good contacts. If the space between the old ball of soil and the pot is large enough, use your fingers to firm the soil. When finished, the new soil should be watered thoroughly, which may rewuire several waterings. At the same time, any old or broken leaves should be removed and the rim of the pot covers with aluminum foil or scotch tape. One important point should be kept in mind. A shift from a 2 ½-inch pot should not be made into a larger container than a 4-inch pot. Otherwise there will be too much soil, which if it remains too wet for any length or time, will cause failure of roots to grow into it. If it becomes necessary to shift from a 4-inch pot to a larger one, a 5-inch pot should be used, not a 6-inch. This is particularly important if the Pot is placed in another container and thus cuts off evaporation from the pot. Since such a shift allos only about ½-inch on the side of the ball, firm the soil only enough to remove excessively large air pockets that may be present.
After the 2 ½-inch size, it is best to use an African violet pot. This is more shallow than the “standardâ€? pots and permits better drainage and exposes more surface for water escape at the top. A good way to tell when an old plant needs repotting is to check on roots coming through the drainage hole. If they are, this usually indicates that the ball of soil is solid with roots.
Watering Watering of African violets is no different than many other plants. They can be watered overhead by means of a long-spouted watering can or they may be subirrigated from below by letting the water come upward through the soil. The better method to use depends on the kind of soil and on the attention paid to the plants by their owner. Actual watering may be compared to the proper and improper way of feeding yourself. If you eat here meals a day at regular intervals, you use up enough food to supply you with energy until the next meal. The same is true with watering plants. Give then a good soaking to wet the entire pot and have some surplus running out the drainage hole. Do not water again un-
til the soil starts to become slightly dry. The usual method of wetting the top of the soil frequently may be compared to lunching between meals. The results are similar: you would suffer from too many snacks, and a plant would likewise suffer from too much water care. Much has been said about eh quality of the water to be used. It is true that if rain water were available to everyone, it would probably answer the purpose best. Since, however, the task of saving such water would be too involved in the average home, city or well water will answer the purpose adequately. It has been said that chlorinated water is injurious to plants, but there is no basis for this except when the amount of chlorine is so high that water cannot be used for drinking. Even then, very little damage to plants may be expected. The same is true for fluorine, which is now being added to city water in some areas for health purposes. Avoid, however, continued use of water softened by sodium. Sodium destroys the granular properties of soil aggregates, is not essential for plant growth and contributes to the soluable salt level in the
soil. Where hard water only is available, if sufficient humus is mixed with the soil, there is little likelihood of trouble. If you are at all in doubt about your water supply, consult your local florist or your state agricultural experiment station.
Overhead Watering. The safest method of watering is overhead, provided you have learned how often to do so and provided you avoid the use of cold water. To give exact rules for frequency of watering is impossible since that depends on the soil used, the location of plants in the home relative to heat source, the temperature used, the amount of humidity in the air. In general, however, if the solid drains well, your plant needs water if the surface is dry. It is well to look at the plants daily, although they may not need attention more often than every three days in some cases. The higher the humidity around the plants, the less frequent will the watering have to be. Cold water applied to the soil of plants does no harm, but when it hits the warm foliage it will cause ring spots. To avoid this, water early in the morning, if possible, avoid hitting the foliage, or to be on the safe side, use warm water about 10 degrees above room temperature. Then any splashing on the foliage will do no harm. Caution should also be taken to keep water out of the crown of the plants as this may cause rotting. 21
Watering should be thorough. Pour enough water on the plant so that water runs out of the drainage hole in the bottom. To make sure of wetting all the soil, repeat the operation by watering twice and allowing the pot to drain. Then if your plant is setting on a saucer, empty the excess water from the saucer, as well. If plants are set on pebbles in a watertight pan, such precautions are not necessary. The excess water will evaporate and provide additional humidity.
Subirrigation.
Watering from below is used by many growers and is successful, providing precautions are taken to avoid saturating the soil to the point where air is excluded. Oxygen or air is very essential for root growth. When the spaces between soil particles are fi8lled with water, as can happen in excessive subirrigation, the roots will die. The following methods of watering form below are used: (1) Saucer Watering consists of setting a plant in a shallow saucer or pan filled with water to allow the water to rise through the soil. As soon as you wet the entire ball through and moisture can be seen on the surface, empty the saucer of any excess water. This removal of excess water is important (2) Wick Watering is similar to sauce watering except that water is transferred by movement through the wick instead of contact between soil and water. Such equipment is on the market in the form of pots with wicks. The wicks are
made of fiberglass or sometimes cotton and may be found in any garden store, as well as variety stores. To make your own self watering pot with a wick, take a wide glass jar big enough to hold the pot in which you have planted your violet. Buy a wick and insert one end about 1.2 inch into the drainage hole. The end should be raveled out so it makes a mass of strands. The unraveled end of the wick is placed in contact with the soil. To keep the pot itself from direct contact with the water below, set it on an inverted top of a can, through which a hole has been made for the wick. The water in the glass jar or reservoir should be kept replenished so that the wick never dries out. This method is almost automatic and eliminates overhead watering. It is also possible by this method to control a certain extend the quantity of water in the soil by adjusting the depth of the water in the container. (3) Constant water level is a modification of the wick method. No wick is used. A watertight container about 4 inches in depth and should be filled with 2 inches of gravel and water. This should be covered with about 1 inch of sand. Porous pots are set on top of this sand, and water comes up through by capillarity. In this case the level of water is extremely important. Perfect contact between the sand and the pot is also vital.
Usually the water level should not be lower than the bottom of the sand. If it gets too low, no capillary action will take place. If it gest too high, the soil will be waterlogged. Likewise, if contact is lost between the bottom of the pot and the sand, no water will go up. If all the precautions are taken this is a good method. Occasionally it is well to water overhead by lifting the pots and allowing water to drain. The same procedure should be followed when fertilizing. After that, make sure that contact is established between the pot and the sand below. In general, these sub-irrigation methods have the advantages of eliminating worry about wetting the foliage. With these methods the soil does not compact and thus contains more air. On the other hand, there is the danger of overwatering and also of bringing up fertilizer salts, which are toxic materials to the surface of the soil and the rim of the pot, which may ultimately cause damage to foliage. In all cases of sub-irrigation use the foil around the rims of the pots as suggested previously. This prevents contact between the leaves and the salts, which rise upward with the water. Occasional watering from the surface to leach out salts is also recommended.
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Illustrations on watering
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Illustrations on watering
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Diagnosis of Troubles Like many other plants, African violets are subject to various diseases, insects, and allied pest- in addition to mismanagement troubles. Since the last are most easily corrected by careful handling, let us examine them first.
Gases.
Where artificial gas is used in fireplaces or for cooking, considerable trouble arises in getting the African violets to flower. There are really no corrective measures for that except ventilation, which of course, is not feasible except during warm weather. Natural gas does not contain the harmful ingredients of the artificial gas, so little trouble is experienced from that sour. Make sure what your gas source is before indulging in the culture of African violets.
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liage us indicative of lack of fertility, usually lack of nitrogen. Gradual yellowing of older leaves, progressing to overall light green color and smaller leaf sze is also indication of nitrogen deficiency. Plants differing form lack of nutrients will start to develop good color within 5 to 7 days after an application of fertilizer. Should be applied with caution, however. Too much fertilizer may also result in light foliage color because of damage to the roots.
Ring Spot. This trouble has been mentioned and may be corrected by avoiding the splashing of cold water on the foliage. If you would like to see how his works, take an ice cuve and let the cold water drop on the foliage.
Leaf Bleaching.
Overfertilization.
This may be due to too much light or to lack of fertility in the soil. If you keep your plants near a window where the direct sunlight strikes them, be especially watchful that they are shaded from it, particularly after a protracted dark spell. The leaves get soft, and bright sun will burn and cause mushy spots. Grayish fo-
Over-fertilization may appear in the lengthening of the petiole of the leaf and making it soft, although inadequate light may also be responsible, as well as overwatering. Brown areas on the edges of the leaves or marginal burning are pretty sure signs of a quick overdose of either nitrogen or potassium. A thorough wa-
tering several times in a row should clear that, but before resorting to this measure, have your soil tested.
Leaf Stalk Rot. As described previously, this usually happens in plants in clay pots, which are watered from below. The water rises in the soil, as well as in the sides of the porous clay pot, and with it carries some of the fertilizer salts which are in the soil. These form a toxic crust on the rim of the pot, and any leaves coming in contact are injured and a brown rot develops. The remedies are simple: either don’t water from below or cover the rim of the pot with aluminum foil or scotch tape. If plastic pots are used, toxic crusts are no problem.
Bud Drop. This may be caused by various conditions. A major cause is ethylene gas; others are too dry an atmosphere, too much fertilizer – especially nitrogen – overwatering, extreme changes of temperature and attacks by thrips.
Stunt. This is a virus trouble and outwardly looks like the effect of mites. The young leaves are thickened and brittle and become dwarfed and light colored. However, they tend to curve downwards instead of upturning as in the case of mite trouble. Likewise, instead of upstanding hairs, there is an appearance of glassiness. There is no remedy except to burn the plants.
Stem or Crown Rot. Occasionally we run into a rotting of the stem of the entire plant. This is caused by several fungi (parasitic minute plants), which enter the tissue and cause death of the cells inside. For control use Terraclor, Semesan, or Panodrench. Burying the crown by deep potting is a contributing factor. Adherence to the practice of soil sanitation by sterilizing containers and drainage material will reduce such troubles to the minimum. Overwatering or waterlogging of the soil is conductive to such troubles. In many cases it is best to discard the plant so the trouble will not spread to others.
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Mildew. This is a disease caused by another fungus which appears as grayish patches of fuzzy growth on leaves, flower stalks and the flowers themselves. Sulphur dust or spray, Actidone, Karathane, mildew, Omazene or phalthan sprays are good mildew control materials, although sulphur may bleach the flowers temporarily. Apply dusting materials lightly with a powder puff or by putting the dust into a cheesecloth bag and shaking it over the plant. Wettable sulphur can also be purchased. Dissolve it at a rate of one teaspoonful to a gallon of water and spray the plants with it. Special note: spray solutions should be made with warm water to prevent spotting of leaves.
Mites.
Nematodes.
These minute pests are invisible to the naked eye and are a constant menace to African violets. They occur in the crown of the plant and on young leaves. The symptoms of their presence are: crowding of young leaves, dwarfing and curling of edges upward. The young leaves in the crown appear more hairy than usual and the flower stalks curve and swell. Flowers are small, misshapen and sometimes streaked.
These are tiny worms, known as eelworms, which cannot be seen with the naked eye. They attack the roots and cause swellings known as knots. These prevent intake of water and fertilizers and thus stunt growth. Some species attack the roots and cause rotting. Oc-
There are a number of sprays, which are used for control. Kelthane can be used to control cyclamen and broad mites which injure the young growing portions of the plant. Kelthane, Malathion and sodium selenate control red spider mites,
Pests All materials which are deadly to insects should be handled with care and kept locked away where children cannot reach them
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casionally other kinds known as leaf nematodes cause dark spots on the foliage. Again you may find them as bumps at the crown of the plant. If you notice the leaves getting limp, lacking color with failure to flower, it is well to examine the roots and crowns for telltale signs. The best remedy is a preventative one: soil sterilization, which kills these pests. However, once the plants show symptoms of this trouble they should be discarded, because there is no cure once nematodes are in the plant.
which cause webbing. Other good control materials are Aramite, Chloroben, Zilate, Dimite, and Endrin. These may be purchased at garden supply stores. Thorough spraying into the heart of the plant is necessary, and one application is rarely sufficient. An important warning must be remembered, however, if you use sodium selenate: soils reated with this substance must not be used for producing food or vegetable crops. Sodium selenate used for African violets, is mixed with the soil or applied to the plant’s soil surface. It is absorbed by the plant into its tissues from the soil.
Mealybugs. These are difficult to control because of the waxy, cotton-like substance which coveres the bodies of the insects. They suck the juices and cause malformation of leaves and flower stems. If the infestation is not serious the best remedy is to dip a cotton swab in rubbing alcohol and touch the bugs with it. Malathion or Trithion spray can also be used for mealybug control as discussed under “mites�.
Thrips. These are small, whitish or yellowish insects, which suck juices out of the plant and rasp the tissues, making silvery streaks on the underside of leaves. On
flowers, in addition to streaks, brown spots develop and the flowers drop prematurely because of pollination by these insects. Spraying with nicotine, rotenone or pyrethrum preparations usually gives good control. Malathion is also recommended for thrip control, and regular use of DDT is effective. The best control is a poison known as Lindane, which is used as a spray. If a sprayer is not available, the entire plant may be up-ended and dipped into one of the suggested spray materials, which are available at seed stores, some variety stores and florists.
Aphids or Plant Lice. These may be green, brown or black insects, easily visible. Lindane is an excellent control, as well as Malathion, Phosdrin and Trithion. The plants may be sprayed or dunked in the solution.
Springtails. These are small white insects with a taillike spring, which jump rapidly on the soil and feed on the humus in it. They are harmless but can be eliminated by watering the soil with a teaspoonful of 25% Lindane wettable powder in one gallon of water, or by lightly dusting the soil surface with a 10% DDT dust.
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Images From: Kelsey Balling Michael Krefft Mary Ellen Rynes Chimeraav.com Mahr Arian Kathy Green
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pnwhandbooks.org Sherway Gardens Ruth Hayward Sheryl Normandeau Janna Beckerman
Jennifer Dennis Hannah Smith Dr Wilson Wong Mary Sue Karin Missouri Botanical Garden
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When taking care of African Violets, any new grower, or any experienced grower will need some guidance. This brochure will cover everything one would need to know when deciding to grow African Violets.