Ask the Experts

COMPARE TOPSOIL AND GARDEN SOIL?

Question: What’s the difference between topsoil and garden soil?

Answer: Great question and you would think it would be a simple answer. These terms can mean different things depending on who is using them and how. Sometimes they are used interchangeably.

Topsoil is the upper layer of soil. It is above the subsoil. The logic is the top layer of soil should be the best soil for growing. Unfortunately, it does not always relate to quality. It depends on where or how it was formed. Topsoil in the KC area is very heavy in clay, whereas topsoil in Florida is primarily sandy. Honestly, all it means is it is the top layer of the soil. People jump to the conclusion it is better than something else. Often topsoil in the KC area is not the best for growing plants, but it is better than the subsoil, which can have a higher clay content and fewer nutrients.

Garden soil honestly means nothing. We would think by the name it can be used in the garden and would be better quality than the topsoil. But we don’t know its composition. The thought is garden soil would have more organic matter breaking down the negative effects of clay while holding more water and having better aeration for growth. In most cases, depending on the quality, it is nothing more than topsoil from somewhere that has organic matter mixed in. But that is not always the case.

Clear as mud? The real question is what is in the soil. Topsoil does not always mean better than what you have. My hunch is garden soil is probably topsoil with organic matter mixed in. When it comes to soil, don’t just look at the name on the bag but what is really inside the bag.

MISCANTHUS MISSING THE CENTER, TIME TO DIVIDE

Question: My Morning Light Miscanthus has been in the ground for a few years. This year the new

This liriope is spreading.

growth came from around the edges, and the center was dead. What caused this, and what should I do?

Answer: Many of the ornamental grasses develop what is called an open center as they age. The older parts die out, leaving the healthy growth at the edge. This is common and a sign it is past time to divide. Some varieties are more prone to the open center than others. However, all ornamental grasses will do it over time.

Dividing grasses can be hard work. It is often best to divide more often before the clumps become too big, and harder to get it out of the ground. Dividing is done in late winter or early spring. Cut it back as low as possible, pry it out of the ground, and then replant the healthy outer edge, maybe a 6-inch or so clump. Discharge the dead portions. Avoid too large of a division as you will be dividing sooner than later.

LIRIOPE, TWO VARIETIES WITH DIFFERENT BEHAVIORS

Question: A landscaper planted liriope in my bed a few years ago. Now it is spreading everywhere and looks unkempt. Is there a way to keep it from spreading, or should I just get rid of it?

Answer: There are two common species of liriope planted in our area. Liriope spicata tends to spread by rhizomes and can quickly take a garden bed. The other species is Liriope muscari, which tends to be more clump-forming. Both have their places depending Japanese beetles still a problem. Cherries are hard to grow in KC.

on the purpose.

Spicata is best used as a ground cover. Muscari, especially the variegated form, is often used as a border plant along walks or to edge a garden bed. The trick is to plant the right species for the location.

In your case, it seems the wrong one was planted. Since there is no way to stop it from spreading, removing it may be the best recommendation. Either hand dig and remove or treat with a herbicide. Control with a herbicide can be difficult due to its waxy leaf. Broadleaf herbicides are not effective as it is more grass-like. Glyphosate might be your best bet, but it could take a couple of applications.

JAPANESE BEETLES

Question: The Japanese beetles have returned and munched their way through my garden. I have heard if I crush them, I will attract more to my garden. Is it true they should not be crushed? I get great satisfaction to hear them pop when I step on them.

Answer: Japanese beetles are attracted by a pheromone drawing them to mate. The story goes that if you step on them, it releases the pheromone, and the sex-crazed adults will come hoping to do the insect nasty.

Part of the story is true. Japanese beetles are attracted by the pheromone. But once mated, they are no longer are attracted by the scent. The bad news is by the time you get to them, they have already mated and are now just hanging out feeding, or in the case of the females, laying their eggs. So go ahead and crush away! If it makes you feel good, then stomping them out will have no effect on attracting more.

Remember, if you use the Japanese beetle traps, place them as far away a possible from your garden as they draw in more adults to feed – a rookie mistake.

DESIRED SWEET CHERRIES DIFFICULT TO GROW

Question: I enjoy eating sweet cherries when they are available in the stores for a short time. Can I grow sweet cherries in KC?

Answer: Sweet cherries are delicious but challenging to grow in KC. They are not as adapted to our ever-changing weather patterns. On the other hand, tart cherries used for pies, cobblers, and jams are some of the easiest fruits to grow.

Sweet cherries would prefer to grow in loamier, slightly acidic soil. Their root systems need excellent drainage and even moisture. Cold tolerance could be an issue as they do not tolerate the swings in temperature in the fall and spring. They will grow here but often do not thrive and are short-lived. If you try, keep in mind many varieties are not self-fruitful, which means you will need two varieties. Recommended self-fruitful varieties by K-State and MU are Stella, Black Gold, and Starkrimson.

DENNIS PATTON Horticulture Agent

Dennis Patton is the horticulture agent for Johnson County K-State Research and Extension. For free information fact sheets, visit www.johnson.ksu.edu, or call the Extension office at 913-715-7000.