FAQ: Page 8

The Violet Barn

Question: After repotting, some of my miniature violets will begin to grow smaller than normal leaves in the plant's center. Any explanation?

Answer: We find that this is sometimes the case with some of the heavier blooming varieties. To start with, prolonged, heavy, blooming seems to divert the plant's energies away from foliage growth. This is especially a problem when heavy bloom is concentrated over the center of the plant--there just isn't enough light or room for new growth to fully develop. This is true for both minis (semiminis) and standards. This is one reason that "showplants" are disbudded--to promote foliage growth.

This can be a problem following repotting, particularly if done while the plant is in heavy bloom (which was true for this grower). Having pruned away a portion of the root ball, the plant now has to maintain a head of bloom with a smaller root system. The consequence is that new foliage development suffers. For miniature varieties, where the head of bloom is large, relative to the size of the plant, this seems more likely to occur. Our answer is to remove all bloom when repotting, for any size variety (we do leave the smaller buds). This allows the plant to reestablish its root system and grow some new foliage before it needs to support much bloom. Those small buds that remain will become blossoms soon enough.

Question: My violets develop plenty of buds, but many of them don't open into flowers. The humidity level is quite low (20-25%) in my home. Is this the problem?

Answer: Low humidity can cause buds to "blast" (not open) or not fully develop into blossoms. The solution, of course, is to raise the humidity level in the area surrounding your violets. An easy way to do this is to grow plants above, or on, a moist surface. If you top water, this can be done by placing pots atop a tray of pebbles or gravel. Fill the tray with water, to just below the surface, so that pots don't actually sit in the water. The evaporation of water from the tray will increase the humidity level surrounding the plants.

Watering by capillary mats will also increase humidity. Here, pots are place upon a damp blanket (use those made from man-made fibers). Plants draw moisture through the drainage holes, where soil is in contact with the damp blankets. Again, humidity is increased as water evaporates from the blankets. Community wick-watering of plants also will increase humidity. To do this, place a sheet of "egg-crating" over a tray holding water. "Egg-crating" is the plastic grid used in florescent ceiling lighting, is sold in most lumber yards or home centers, and can be cut to size. Pots sit atop the crating above the water in the trays, with the wicks extending through the crating and into the water. Water is drawn through the wicks and into the pot. The standing water in the trays will also increase humidity.

Lastly, your violets themselves provide humidity as they transpire moisture through their leaves and water evaporates from the soil surface. Grouping plants together will take advantage of this--but don't overcrowd. For those of us with really large numbers of plants, low humidity never seems to be a problem.

Question: I root my leaf cuttings in water. The leaf will produce a plantlet, but when I pot it into soil, it dies. Should I remove the mother leaf when I do this?

Answer: Though leaves may be rooted in water, there are disadvantages to this method. The root system that develops is one that is best adapted to growing in water. Potting the plantlet into soil means adapting to a much different environment. Also, you'll notice how the roots "cling" together when removed from the water. Without a spreading root system, which maximizes exposure to moisture and nutrients, the plantlet is at a further disadvantage when potted into soil.

Partly for these reasons, most growers root leaves in something other than water. Any very light, porous, medium will work. These are made up mostly (or entirely) of vermiculite and perlite. Besides producing more plantlets per leaf, these media will produce better developed root systems that adapt easily to potting into soil.

As for removing the mother leaf, this can be done when the plantlet is potted alone. If you're concerned about the plantlet's survival, you can place it in a clear sandwich bag for a few weeks. The high humidity within the bag will keep the plantlet from wilting. Further watering shouldn't be needed if the bag is sealed--if it's too soggy, it may rot.

Question: Is there a way to force African violets to bloom? My plants do not start blooming until they are mature plants. I have seen very small plants in bloom. Are these early bloomers "forced"?

Answer: Early blooming is a product of two things: the genetic predisposition of the variety, and good culture. Some varieties just bloom earlier than others. As hybridizers, this is a trait that we look for. Some, in fact, begin to bloom just shortly after being separated from a leaf cutting. We will actually remove the buds on these varieties to allow them to develop some foliage first. These varieties are also often the ones being sold, since commercial growers are interested in a quick turnover--varieties that take up growing space waiting to bloom are more costly to grow.

Good cultural conditions, from the very beginning, are also important in early blooming. For example, we fertilize normally from the beginning. Leaf cuttings and small plantlets are fertilized as much and as often as mature plants. This is contrary to the opinion of some. Our feeling is that a growing plant needs food, no matter its size. Light, water, temperature, etc. are also the same as for mature plants. This isn't "forcing" in that nothing different is being done for younger plants. What's being provided are the optimal conditions to allow young plants to reach their full potential at their earliest age.

Question: I recently purchased a species violet (S. velutina) at a local show, and discovered that it had been wicked. Can I repot it into my usual soilless mix (and top water) without danger of losing it?

Answer: Certainly. If anything, we find that most of the species violets do a bit better if not kept overly moist, and like a vely light, porous soil. Most grow more compactly than the modern hybrids, and seem to have a smaller root system. For this reason, we prefer to top water most of our species, and are careful not to use too large a pot. Most seem happy in 3" or 4" pots (grown as houseplants, and not for show). Having said this, wicking is perfectly acceptable, so long as a very light soil mix, with plenty (50% minimum) or perlite being used.

Question: Which window should I use?

Answer: Whichever window works. Since every window is unique, there's no simple answer. It's not the window, but the environment in the window area. What you want is plenty of bright light, but not direct, hot, sun. Which window provides this depends upon the season, climate, type and cleanliness of glass, obstructions outside the window, and more. If there is too little light, your violets may have healthy, green foliage, but few flowers. Leaves might also grow upward, rather than flat, and be longer than normal. A violet receiving too much light, might exhibit tight, crowded growth, that will grow flat or hug the pot rim. Leaves might be yellow or bleached if sunlight is too strong or warm. Start with a window that you believe provides optimal conditions, and if your violet isn't happy, move it to a better spot. Also remember that the best window may change depending upon time of year and weather conditions.

Question: I have a violet that, about a year ago, developed a variegated leaf, then another, until all were variegated. I started new plants from those leaves, but they all grew green leaves. The variegated suckers also didn't seem to produce much variegation when rooted. Do you have any ideas?

Answer: Our guess is that this is just another kind of genetic mutation. We've had plants do the same, sometimes where the entire plant was heavily variegated. Except for one instance, we've never had any success in propagating variegated plantlets from leaves or suckers. Usually, given enough time, the original variegated plant also loses much of its variegation, or reverts back to solid green foliage. It's really too bad, since a few of these plants have had absolutely exquisite variegation. If the variegation really is distinctive, keep trying. After all, much of what we have in today's hybrids first showed themselves as mutations--'Tommi-Lou' variegation and yellow blooms being two very notable examples.

Question: I have brown scarring on the backs of my lower leaves. Why?

Answer: This is a question we received by phone. We didn't immediately have an answer until he happened to mention that he grew in clay pots, and also wondered why the bottom row of leaves was bent over the pot rims. The culprits, of course, were the clay pots but, since we hadn't grown violets in these in nearly 30 years, it didn't quickly come to mind. Besides their weight, expense, and difficulty to clean (and keep clean), scarring of the petioles and undersides of leaves can be a problem presented by clay pots. Being porous, the pot absorbs the water (and whatever is added to it). The water will evaporated and the pot will dry, but some of the fertilizer remains within the clay, most noticeably on the pot rim--like a ring on a bathtub. These accumulate over time and can burn, or "scar" the undersides of leaves and their petioles when they come in contact with the pot rim. This can be more of a problem for African violets, which produce leaves in a flat rosette, than for plants that grow more upright.

A solution for those who prefer to grow violets in clay pots is to create a barrier between the leaves and the pot rim. One simple solution is to cut thin strips of aluminum foil and fold them over the pot rim. Using a glue gun, you might also apply a thin bead of glue around the pot rim--or apply a bead of silicone of bath-tub sealant. Another is to cut thin nylon tubing (like the kind found in tropical fish stores), lengthwise, then secure them to the pot rim. Some exhibitors use the latter method even with plastic pots, since it helps protect the lower leaves of large showplants from the sharp rims on plastic pots ("rolled", or rounded, rims are better for this reason).

That said, clay pots are attractive and can make plants look even more so. Just be aware of their shortcomings and adjust your culture accordingly. Because they are porous, soil will dry much more quickly than when potted in plastic. Water is evaporated only from the soil surface with plastic pots, but from soil and pot surface with clay pots. This means that plants with small root systems, like miniatures, will dry very quickly in clay pots and will need to be watered quite frequently. Also, very light, porous, soilless mixes that work so well with plastic pots may dry too quickly in clay pots. A heavier mix that retains more water may work better when using clay pots, unless one plants to keep the plant and soil constantly wet. Finally, if you want the advantages of plastic pots, but the appearance of clay, you might simply grow in plastic and slip plant and pot into a slightly larger clay pot!

Question: My sister sent me some "Neem oil" to use for powdery mildew, but I haven't a clue how to use it. Could you tell me?

Answer: "Neem oil" is processed from seeds of the neem tree, native to eastern India and Burma, and is a wonderful product that can be effective as an insecticide, miticide, and fungicide and is safe for home use. It biodegrades quickly, and exposure to neem oil poses no threat to humans or other higher animals, or to "beneficial" predator insects (only to those who feed on plants). Though it doesn't directly kill plant-feeding insects, it does act as an irritant, discouraging them from feeding on the plant. For this reason, it's best used regularly as a preventative, or to attack pest problems in their early stages.

We've found its best use is as a treatment for powdery mildew, the very fine, white powder that appears on leaves and, sometimes, blossom stems. Though powdery mildew rarely will kill a plant, it will scar the surface of leaves and lead to short-lived blossoms. It tends to be a particular problem when there is cool, stagnant, humid air. Spraying with neem is an easy, immediate, non-toxic solution for dealing with powdery mildew on a large number of plants. There is minimal damage to open blossoms (a few varieties appear more sensitive), and leaves will look shiny and clean.

We spray with 100% pure neem oil, at a rate of 1 tsp. per quart of water. To this, add 1/4 tsp. of liquid dish soap, which is need to mix the oil well in the water. If the oil is very thick, use warm water when mixing. Spray all plant surfaces generously with a fine mist. Best of all, it's not toxic to humans--we don't use either masks or gloves when using it. That said, don't be so careless as to swallow it or spray it into your eyes (not lethal, but not pleasant either). As for the odor, it smells a lot like sesame oil. To store neem oil, keep at room temperatures (it thickens if chilled), and shake well before using.

Question: I grow some of my violets in a window and they do well there, except for the winter when they don't seem to bloom very much. I've added florescent light above the plants and really like how they look with the extra light, especially at night or when the days are dark. Would there be any problem in keeping the light on all the time?

Answer: So long as the light isn't too intense, probably not, at least during the winter when you don't seem to be getting much in the way of natural light anyway. Though prevailing wisdom says otherwise, our experience is that violets can be successfully grown even when not given periods of darkness. We have to areas in our shop where many plants, including violets, are grown with 24 hours of light. Both of these receive light from both natural and artificial sources. We do this for much the same reason--it makes the shop windows more attractive at night to passersby. Of course, if you are doing this for your own pleasure, there's no need to keep plant illuminated while you're asleep!

As for whether your violets benefit, leave this decision up to them. If they bloom and the foliage is green and grows well, then the plant is happy and the light is fine. If they are receiving too much light, as might be the case during times of the year when there is more sunlight, foliage may become pale and brittle, new growth may become crowded in the plant center, and leaves may "hug" the pot. If this becomes the case, reduce the time and/or intensity of the artificial light you are providing.

Question: I have a couple of violets that always seem to get extra sets of leaves growing from the center of the plant. Eventually, I have to divide these plants when they get bigger but the problem will reappear. What can I do?

Answer: Unfortunately, "double crowning" (suckering in the plant center) is a genetic condition that won't simply go away by removing the additional center growth or dividing plants. If this has happened more than once with the same plant, it will likely continue to happen. Stress also is a factor, since plants subjected to more of it are more likely to double crown or sucker. Excessive heat, light , or neglect in watering or potting can all lead to excessive suckering and double-crowns. Disbudding can also be a factor, since many plants don't seem to do this unless grown for show and disbudded.

The only real solution is to not grow these varieties, or at least not to propagate using these plants. If others grow the same variety without having this problem, you might try to acquire a plant propagated from them. They may have a different genetic "strain" of that variety that is less likely to double-crown. We've had some older varieties that have developed this problem, and will propagate them, select those plants that grow the best, then propagate only from those, and so on. If we're lucky, we can eliminated the problem, given enough time.

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