Figure 20 small pony tail palm tree in plastic pot (source-google images

• Replacement required after every 18 months. • These are an excellent choice for initiating the growth from the seeds. • These are inexpensive, and have low heat output which makes them eligible to place near plants and avoid any burn or harm to plants. • Disadvantage - these bulbs have low light intensity. Thus, they can only grow a plant till 8-10" height. They are not efficient to grow tall plants as the light won’t reach the lower part of the plant.

o Metal Halide bulbs-

• The blue end; produces compact, leafy growth. • Agro sun gold halide bulbs are colour-corrected to give off more red/orange light; • Replacement required about once a year. • Good choice for a light display in a living area.

o High-pressure sodium (HPS).- • the red/orange end which promotes flowering • replacement required after every 18 months • not flattering in a living room • Lack of blue spectrum light makes plants leggy during the vegetative growth stage.

o Metal halide helps to promote foliage, then switching to a conversion highpressure sodium bulb to encourage flowering. This helps in fast growth and increase flowering by 40 %.

o For reducing the effort in light maintenance, enhanced/corrected bulbs can be used. These are high-pressure sodium son Argo bulbs. They provide 30% more blue spectrum light than standard HPS bulbs.

o Light movers- as the name suggest these are devices which is always in motion and don’t stop at a particular point helping all the plants to get light. These devices increase the area coverage without using much electricity. It directs light at all angles and helps in strong growth at lower levels.

2.3.2 Indoor air

Indoor plants need constant ventilation. Good ventilation is required to maintain normal transpiration rate for better photosynthesis process. The speed of air flowing through plants should not exceed 1.5 m/sec.

HVAC grillers near plants can end up drying or even burning foliage.

Indoor Air Pollution:

VOC (volatile organic chemicals) can be removed with the help of foliage plants. Some VOC's found indoors which can be removed using plants are: 1. Formaldehyde 2. Xylene/ toluene 3. Benzene 4. Ammonia 5. Alcohols 6. Acetone

Hydrocarbons damage plants.

2.3.3 Temperature

The suitable temperature ranges for indoor plants are:Day temperature range - 18 to 24 ℃ ℃ Night temperature range - 16 to 18 ℃ ℃ Plants should not be kept near heating or cooling vents. An immediate change in temperature can injure plants’ foliage. But, when air conditioning systems are closed inside a hermetic space, the temperature takes time to change, thus not affecting the plant. But, most of the indoor plants should be kept away from HVAC vents to avoid that sudden change in temperature.it is suitable to provide outdoor ventilation. Temperatures below 10 harm plants and lead to dropping of their leaves. ℃

2.3.4 Humidity

Suitable relative humidity ranges are:For foliage plants - 40% - 60% (not less than 25% R.H.). For Cactus and succulents - 5% - 15%.

Humidity can be increased by placing plants in a tray with 2 or 3 inches of wet gravel or grouping plants together. Evaporation from the trays and pots increases the humidity around plants but the danger of water clogging and rotten the roots should be kept in mind before watering the plants.