Question:  I wick-water my plants and have noticed very tiny, thread-like insects hopping around on the surface of the soil and sometimes in the water.  How do I get rid of these?

Answer:  What you most likely have are "springtails", which are long, thin, grayish-white insects perhaps 1/8" long.  They can occasionally "hop", but often just wriggle around on the soil surface.  Don't be overly concerned with their existence, first, because they usually do little harm to your violet, and second, because they are easily gotten rid of.  Springtails feed on decaying organic matter in the soil and usually will damage the violet's root system only when there is a pre-existing problem such as root rot.  To eliminate them many recommend a Malathion or Clorox drench, but we find they can be easily eliminated without the use of any chemicals.  Simply let the soil go dry before watering.  Springtails thrive in wet soil, and if let dry thoroughly (but before wilting) you'll find that they will soon disappear.

Because plants that are "wicked" stay constantly wet, springtails can often be a problem for these plants.  If you decide to wick-water, let the water reservoir (and soil) go dry before refilling.  Besides controlling the springtails population, your violets will appreciate the short vacation from constantly wet feet.  The soil will stay fresher longer and your violets will be healthier.  In any event, we would strongly recommend not using (toxic) chemicals to control a problem when a nonchemical alternative is available and just as effective. 

Question:  My violets have seen to suddenly stopped growing.  The centers are tight and the new leaves seem to be deformed.

Answer:  This question is one that we recently received by phone and that we found particularly interesting.  The answer was obvious, but didn't come to mind until the conversation was nearly ended and the critical information was finally divulged.  The problem in this case was very acid water, or too low a pH.  Neutral pH is 7.0 and violets prefer water and soil to be neutral to very slightly acid, in the approximate range of 6.7 to 7.0.  A pH below 7.0 is considered acid, and above 7.0 is alkaline.  If the soil/water becomes too acid or alkaline, nutrients in the soil become less available to the plant, so that even a well fertilized plant can suffer from malnutrition.

This particular grower had always used rain water to water her plants.  Rain water can often be quite acid, but for this grower it had never presented any problems over years of use, and we had eliminated all of the other likely causes of the problems.  it was then revealed that the water had been collected as runoff from the roof, and that the home had just been reroofed.  It was only then that her plants had begun to show signs of distress.  Coincidentally, at that time we were having gutters added to the back of our barn, to keep water from running off of the roof and onto the glasshouse that was being built below.  I had been told that the roof shingles would make the runoff very acid, and had been warned that the acidity of the runoff would etch the glass over time.  The answer was suddenly very obvious!  The water that was being used to water her violets was now too acid.  If it were to be tested, it's likely that the pH would be far below 7.0.  The previous, very old, roof had likely had enough of the acidic chemicals washed away over the years to make water collected from its runoff relatively harmless.

Even rainwater not collected this way can present problems.  I learned this when I moved to our present home, in a relatively rural area removed from industry or heavy traffic.  Water that I collected in standing (plastic) barrels was not as clear and clean as expected.  Along with the rain water was a surprising amount of soot and grime--it certainly was far from pure.  Of course, "city" and well water can also have their problems.  In any event, it's always a good idea to have the pH of both your soil and water tested, particularly if the source of either has changed.

Question:  I see all kinds of advice about growing under lights, but no one has committed themselves as to what type of florescent to use, "warm", "cool", or "grow-lights".  Would you help?

Answer:  This is a subject which requires more than a paragraph or two to adequately address.  We'll keep the discussion simple for this reason (and because we're far from experts in this area).  Basically, the discussion revolves around two considerations: the light's "color" distribution and intensity.  Very simply, light of different wavelengths ("color") are absorbed differently by the plant's leaves for photosynthesis (for growth).  It's been found that light in the blue and red spectrum are most used by the plant.  Artificial lights producing proportionally more light in these colors then, will presumably be more beneficial for the plant.  Incandescent lights provide plenty of light in the "red" part of the spectrum, but these produce too much heat to be used successfully in growing violets--for them to provide enough intensity, they need to be placed close to the plants, but they give off too much heat to do this.  "Warm" and "cool" white florescent bulbs generate less heat (and use less electricity) than incandescents and, though they provide light in the blue part of the spectrum, provide very little "red" light.  "Grow" lights have the advantage of providing much more of this "red" light in a florescent bulb.

In practice, however, light intensity seems more important in growing violets under artificial lights.  Many people grow excellent violets under the ordinary, "cool-white" bulbs available at any hardware or department store.  So long as the plants are getting enough light (duration and intensity), the color spectrum seems of less importance.  Our personal experience has been that there is little apparent advantage to using any particular type of florescent bulb.  We've often grown our best showplants under supposedly the worst light--"cool" white bulbs.  We do use "Gro-Lux WS" bulbs in our shop, but only because these bulbs most closely approximate sunlight so that the "perceived" color that the customer sees in the shop is close to what they'll see at home in their window.  These bulbs are also much more pleasant to work under for 12 hours a day.

Finally, don't confuse light "intensity" with "efficiency".  A bulb using less electricity (watts) may simply produce the same light intensity (lumens) more efficiently.  Again, why not save money?  These measures can change bulb to bulb, so read the label when purchasing.

Question:  When should I repot a trailing violet into a larger pot?

Answer:  This depends upon how you wish to display the plant.  If you wish to grow the trailer as a "hanging" basket plant, you should use a smaller pot and let the "runners" trail over the pot's edge.  A standard-size (larger leaved) variety might perhaps need a 5" to 7" pot when mature.  Miniature and semiminiature varieties can be grown in a smaller pot.  Shallow pots are best, since a violet's root system is relatively shallow, even for larger plants.  Trailers grown this way often do best in natural (window) light, since the vertical space isn't available on a light stand.  It's also necessary to provide plenty of light from both the top and sides, to keep the plant from getting a "straggly" appearance, and this is best provided by a large window.

The other option is to grow these varieties as a "ground cover".  Pot trailers into a wider pot as the runners begin to creep over the edge of the existing pot.  When placed into a wider pot, the runners will simply continue to grow along the soil surface, rooting and producing new runners as it goes.  Again, be sure to use shallow pots.  Grown this way, the depth of the pot should be no more than 3".  Since wide, but shallow, pots can be hard to find, we use saucers with holes drilled into the bottom for drainage.  If deeper pots are used, add some drainage material, such as perlite, in the bottom when potting.

Question:  My Streptocarpus has irregular sections that are missing from the edges of the leaves, as if something had been eating them.  Any ideas?

Answer:  Actually, this is something one of our employees experienced with a plant she had taken home from the shop.  We've also been told similar stories by some of our violet-growing friends.  A week or so after telling us this, she brought in a small, black, insect in a plastic baggie (dead, of course).  She had found it on the plant and wondered whether it could have been the culprit.  As it turns out it was.  We couldn't identify it, but knew who could.  It just happened that a large conference was being held by a group of entomologists and plant pathologists in Rochester.  Being only an hour's drive away, they had scheduled a tour of our shop.  One of them quickly identified the insect as the "black vine weevil", a black, wingless weevil about 3/8" long.  All are female, do not fly, and disperse by walking or are transported by man or on infested material.  Adult weevils feed on foliage, chewing out notches.  Damage is usually not fatal, but often is unsightly.  As larvae, the grubs feed on roots and underground stems, and can be more damaging than adults.

These are most commonly found on outside plants, but they can become nuisance pests when found indoors.  Fortunately, infestations on houseplants are normally small, and control is best accomplished by removing adults by hand when found, even if the appear to be dead--it seems that the adults will "feign death" when disturbed!  In any event, this is not likely to be a widespread problem for violet growers, but this mysterious plant damage has been described to us before.  In this one instance, it was nice to have the mystery solved.

Question:  I'd like information regarding ratio of pot size to plant.

Answer:  This is probably the most frequently asked question in our shop.  One of the most common mistakes the novice grower makes is to pot their violet into too large a pot, assuming that every repotting means potting into the next size pot.  Having said that, it's not true that an African violet needs to be "pot-bound".  What a violet needs, in fact what most houseplants need, is a pot just large enough to accommodate its root system.  It is the size of the root system that determines pot size, not the size of the plant.  The example we like to give is that of cactus.  It may be larger than the person growing it, but its root system could fit nicely into a 8 or 10" pot.

Generally speaking, most standard varieties, when grown as houseplants (not for exhibition), will do quite well in a 4" pot.  Most semiminiatures can be grown in pots no larger than 2 1/2", and most miniatures in 2" or 2 1/4" pots.  Since violets tend to be relatively shallow-rooted, azalea pots (pots slightly less deep than wide) are preferable.  Unless you notice that the root system is crowded in its present pot, there's no need to use a larger size.  this would be the case if you noticed very dense root growth around the outside of the root ball when the plant is removed from its pot.  No matter the size of the pot, violets normally should be repotted into fresh soil, at least twice a year.  This will allow new roots to grow, keeping the root system, and therefore the plant, healthy.

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