Caring for Plants in the Home Q. 21...

21. Q: Why are dracaenas (corn plant and marginata) dropping leaves?

A: Overwatering is a possibility. check the root system. These plants need a lot of humidity and they should be kept away from a heat source. They also require moderately bright light. Leaves drop from the bottom of old plants making them leggy. Could air layer and start new plant. They also require more fertilizer than most houseplants. The new leaves will rob fertilizer from the older leaves so the older leaves turn yellow then brown and drop off.

22. Q: Older leaves on ficus tree in greenhouse have brown spotches on back and leaves eventually fall off.

A: Check for scale insects. If you can remove brown spots it is scale. Generally ficus looses leaves when it is moved from one location to another and there is a change from more to less light. Ficus needs bright light and plenty of water. Older plants lose old leaves as new ones come on. Ficus also have a disease called Oedema which is a nonparasitic disease. When the relationship of the plant with water are abnormal as under conditions of exceptional humidity, small masses of tissue may expand and break out on the surface causing a watery swelling or gall. Frequently the exposed surface becomes rusty in color so that the lesion may be mistaken for a rust caused by a fungus.

23. Q: What houseplants help 'clean the air'?

A: Any plant will help clean the air. Plants with large leaves such as fiddle leaf fig, philodendrons and dumb cane (dieffenbachia) are a few examples. The bigger the leaves the more cleaning effect they have.

24. Q: Can you prune indoor ficus tree?

A: Yes. Can be pruned rather severely. Prune as you would a normal tree. Thin out branches; do not top the tree!

25. Q: Fronds on palm are turning brown. What is the cause.

A: Needs lot of water and humidity but can not stand wet feet. Check the root system for overwatering. Roots will be dark brown to black. The skin of the root can be slipped out leaving the center part of the root -- overwatering caused this. After the soil dries out, drench with a root rot fungicide such as Ban Rot or Subdue; follow label directions and control watering and humidity.

26. Q: What is causing black 'grit' or 'soot' at base of a few leaves on fiddle leaf fig plant?

A: It is insect caused probably scale, aphids or whitefly. Any insect that produces honeydew could cause the problem. Control the insect and you will control the sooty mold. In this instance, it is probably scale because it is localized at the base of the leaf.

27. Q: When can houseplants be moved outside?

A: It is best to wait at least until the last frost free date. Better to wait until middle of April.

28. Q: How do you care for African Violets.

A: Very carefully. The African Violet Society likes the wicked type pots specifically made for growing African violets. Most are grown under artificial light unless there is bright natural light; not direct sun however.

29. Q: How do you induce bromeliads to bloom?

A: Patience is needed. As a general rule the minimum time for flowering is three years from seed or about two from vegetative propagules (pups). If your bromeliad is mature and still not showing a flower bud, a change of environment is in order. First apply fertilizer rich in phosphorus. If this doesn't work, try placing the plant into a brighter and/or warmer spot. Should all these techniques fail to produce flowers within a year, it is time for the apple-in-the-bag trick. First pour off any water in the bromeliad cup. Obtain a fragrant ripening apple and enclose it and the bromeliad in a sealed, clear plastic bag. Keep the bagged plant out of the sun, but in a warm place. after one week remove the bag and apple and return the bromeliad to its former location.

This method can be used to force pineapple or any other bromeliad to produce flowers and fruit within one year. The apple while ripening produces a gas called ethylene, which stimulates bromeliads to flower. Most cases of failure occur because the apple is underripe or overripe, at which point ethylene production is minimal. Chemicals are available which produce ethylene, but they are expensive and/or flammable. They are best left alone. If this trick doesn't work the first time, wait a few months and try again.

Forced blooming may produce imperfect blooms or premature blooming in young offsets not yet detached from the parent plant. If you should decide to attempt to force blooming, be sure your plant is at a mature stage and well-established on its own.

30. Q: How do you remove deposits of salts from clay pots?

A: Soak in a solution of one part bleach to nine parts water; This will not completely remove the salts from the clay pot. If the pots are in bad condition from salt build up, it would be best to start with new pots. The pots could also be buried in soil over the winter and they will leach out from natural rain.

31. Q: What causes tips of plants to curl?

A: Many things could. Aphids and other sucking insects such as mites and scale can sometime cause curling. Low humidity, low light, too hot a temperature and over and under watering can cause curling.

32. Q: What is causing ficus tree to lose leaves. Took it outside and sprayed it with Malathion. It has not been repotted in at least 6 years.

A: Ficus are very picky plants when it comes to losing leaves. It has been said many times if you look at them wrong they will drop leaves. Possible causes was moving the plant around; may need to be repotted; drafts going across the plant; change in temperature. Ficus are known to drop leaves in the spring and fall because of the change in the location of the sun. Also over or under watering could cause leaf drop. It is doubtful that Malathion would have caused the problem.

33. Q: Ficus plant has tiny insects and leaves are speckled yellow.

A: Plant has spider mites. Use approved miticide for use indoors. Mites are difficult to control.

34. Q: Gardenia plant growing indoors won't bloom even though it appears healthy.

A: Gardenias kept indoors must have high humidity and cool nights as well as plenty of sunlight. The plant will not set buds if night temperatures exceed 65 degrees F.

35. Q: I recently brought home a bromiliad that's in bloom. How do I care for is plant (water,light,fertilizer)?

A: Bromiliads are good house plants if put in an area with high relative humidity (some folks put them in the bathtub in the restroom!) As with all plants, the more light the better. Filtered (through a tree canopy or curtain) rather than direct light is best to avoid foliage damage or sunburning. Fertilize once every two or three weeks by spraying to runoff with a water soluble fertilizer such as Miracle Grow, Rapid Grow or Peters 20-20-20. Remember, bromiliads are saprophytes and take most of their nutrition through the leaves -- roots are largely for anchorage.

36. Q: I was looking for basic information on growing, varieties and medical properties of aloe vera. Can you help?

A: Aloe Vera or, more correctly, Aloe barbadensis, has been around for a long time. The spiny, yet tender leaves of the aloe plant have been harvested and put to use since the days of the Roman Empire. Initially they were valued for their medicinal properties. In the Middle Ages, however, aloe was an ingredient in the mysterious compounds used by witches and charlatans. In Egypt, aloe is believed to bring good fortune. Often these plants thrive for months, even years, without water or soil.

Although aloes can be started from seed, it is best to obtain young plants, called pups, that develop near the bse of the mother plants. Aloes like sandy, well-drained soil and full sun. In Texas, the desert-looking aloe is often used in rock gardens along with other plants that have unusual shapes or striking configurations. Aloe is winter hardy in zone 10, requires protections in zone 9, and must be brought indoors or protected from freezing throughout the rest of the state including San Antonio some years.

Aloe is ideal as a potted plant. It requires little water and little fertilizer. It can be put on a windowsill that receives direct sunlight, or a coffee table or plant stand that receives indirect sunlight. For indoor culture use a potting mix of 50 percent sand and 50 percent loose soil.

The clear, smooth jelly of the aloe plant is used in the home to reat minor kitchen burns, abrasions and sunburns. Any leaf can be harvested, simply cut one off and peel back a portion of the skin. It dries quickly when applied. Aloe leaves will keep a few days in the refrigerator. Unused portions also can be wrapped tightly and stored in the freezer.

37. Q: I bought a beautiful potted hoya plant from our Horticulture Club here at the University of Missouri -Columbia about a year ago. Since then, it has grown a great deal but it doesn't seem interested in blooming. I keep the soil fairly moist and fertilize with Jobe plant spikes.

A: The Wax-Plant (H. carnosa) grows to 8 feet or more. The clustered flowers are whitish with a pink center. Since your plant is living and growing I must assume it is getting adequate drainage or it would have died otherwise. I imagine that it is not getting enough indirect sun for a long enough period to stimulate bloom. You might try moving it outdoors in the spring and summer and locate it in a place where it gets morning sun and afternoon shade. Keep them in a resting stage during the winter but do not cut off the old flower stalks as they produce flowers for several years once the stalk is formed.

38. Q: I recently found a 2' high poney tail palm in very poor condition (lack of water). What is the proper way to care for this plant? How much water? How often? What fertilizer frequency & strength?

A: The poney tail palm requires relatively little sun and often grow surprisingly well in the living-room, where the atmosphere is usually too hot and dry for most plants. For success with palms in the house a few basic requirements should be remembered. Chief among them is never to allow a palm to be chilled by a sudden cold draft from an open door or window; this will cause the leaves to turn brown and eventually drop. As palms are not expensive in the small sizes, it is better to buy a new one than to endeavor to restore a chilled one. Another requisite is to water thoroughtly whenever necessary, but never to allow stagnant water to stand in the pot or in the saucer beneath it. It is best to water palms from below, by setting the pot in a basin of water, and leaving it their until the surface soil is damp. This treatment once a week is far better than a daily sprinkling of the soil. To keep the leaves free from dust and soot, sponge them frequently with clear water; regular syringing with a fine spray and considerable pressure will normally keep insects such as scale, thrips, red spider, etc., under control.

Repotting should be done only when absolutely necessary, and preferably in spring or early summer. In shifting do not move to too large a pot; one a single size larger than the former containers is about right as palms do best when their roots are confined. The majority of palms succeed best in a night temperature of 60 degrees F. and a day temperature of 70-80 degrees F. This is usually not possible indoors. Periodic fertilization with a water soluble fertilizer is recommended or use a slow-release fertilizer such as Osmocote in the container.

39. Q: My the ficus and one rose have very fine webs on them, and sometimes I can see tiny white specks moving around on the webs. What are these and how do I get rid of the problem? I need something safe for enclosed areas. Also, this same rose plant and a couple others have what appears to be tiny pale spots all over many leaves, looking almost like dust, but not brushing off when I touch a leaf. It is spreading on all the affected plants.

A: You have done the most thorough job of describing the exact symptoms of spider mites I have ever seen. Think about it! A spider has "webs", right. Spider mites are small, almost microscopic, and "move around in the webs". They are white because of the light in which you are seeing them. The multitude of tiny spiders are sucking the juices out of the leaves from beneath. Thus, resulting in the "tiny pale spots all over the leaves but not brushing off". To confirm this, thumb the leaves over a white sheet of paper -- if the "dust" particles run off or move around, you definitely have mites. And guess what spider mites love even more than miniature roses -- that's right, ficus!! Spider mites ARE mites NOT insects so miticides such as Kelthane (Red Spider Mite Spray) should be used every 5-7 days for 4 consecutive days being sure to add two teaspoons of a liquid detergent (Ivory Liquid or Joy) per gallon of spray mixed. Now, if you don't want to use a chemical control you can use an insecticidal soap spray but BE SURE TO USE IT AT LEAST EVERY 5 DAYS. Sprays of both should be directed to the bottom of the leaves and bottom of all leaves must be covered THOROUGHLY if control is expected.

40. Q: I am trying to grow a stephanotis plant. I bought it in late January and the first five leaves grew healthy and well shaped. The last six leaves are growing narrow with wavey edges. They look extremely abnormal compared to the first five leaves. What is happening to the leaves? What type of plant food should I give it? I keep it in our hottub room. It gets some direct early morning sun and I water it only after it dries out.

A: The Stephanotis plant or sometimes called Madagascar jasmine is in the Milkweed Family. It may require more light that it is receiving to grow normally. It is a tropical vine that grows well in containers. It has oval, deep green leathery leaves and small tubular flowers. The blooms are deliciously fragrant and are often used in wedding bouquets. It should get morning sun (4-6 hours) and afternoon shade. Try fertilizing it with a water-soluble fertilizer (Miracle Grow or Peters 20-20-20) every second time you water it and maybe it will stablize in the low light situation.

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