Tight Centers and Hairy Leaves

Question:  Several of my violets have tight centers and hairy leaves.  I may have overfertilized when I switched fertilizers.  But when I read my magazine, the description of tight centers and hairy leaves seems to come up when describing cyclamen mites.  How do I tell the difference?  I do have misshapen blossoms on some plants, but thought maybe condensation was taking place.

Answer:  It’s hard to know for sure, since so many things can cause these symptoms.  A cyclamen mite infestation is the easiest conclusion to jump to but, fortunately, it’s often the wrong one.  If it is only a fertilizer problem, try leaching the plant by running clear water through the soil, then watering without fertilizer for a short period.  The tight center growth should begin to loosen.  Another possibility is environmental.  Both very warm or very cold temperatures can cause tight centers, though “hairiness” of the leaves makes cold temperatures more likely here.  Are these plants near a drafty window or in a cold corner of the basement?  Too much light can cause tight centers, too.

Cyclamen mites are very tiny insects, visible only under magnification, being less than 1/100th of an inch long.  They can be eradicated with minimal plant damage, if the infestation is caught in an early stage.  On the occasions that we’ve had to deal with this pest, we’ve had to use chemicals to eliminate them (yes, we do use chemicals, but only when absolutely necessary).  We’ve had good success with Avid, which seems to be the miticide of choice among larger commercial growers.  Unfortunately, it is costly ($70 or more for 8 oz.) and comes in quantities that most small growers won’t be able to use.  Given its cost, we wouldn’t advise the small, hobby, grower to expose themselves to toxins for the sake of a few violets.

In any event, we’d suggest that you separate your problem plants from your healthy ones.  Investigate one possibility at at time.  If the problem is bad (i.e. more like mites), root some healthy leaves and throw out the plants.  Wash the leaves in a mild soap (like Ivory) and room-temperature water before rooting, and segregate the resulting plantlets until you are sure that they, too, haven’t inherited the problem.  If you must use a chemical, follow all instructions and take every precaution for safety.  Since their life cycle is about 14 days, repeated treatments will be necessary to eradicate them–say, at least 3 applications at weekly intervals.

Dark ‘Staining’ or Mottling on Leaves

Question:  Our club is growing ‘Rob’s Sunspot’ as our project plant.  Many members are experiencing “red staining” on the plant leaves, though the variety description doesn’t mention this.  Is this a genetic condition?

Answer:  Yes, this is a genetic condition.  This registered variety is described as a “double white star with bright red mottling”.  Multicolored varieties, such as this one, often exhibit mottling in their leaves–the “red staining” described in the question.  Many varieties with such multicolored blooms will also sometimes show mottling in their leaves. 

By their nature, multicolor blossomed varieties are more genetically unstable.  This is the small price we pay for the beauty of the flowers.  Personally, we’ve found those plants with mottling in the foliage make the prettiest plants, since the coloring in the foliage usually means more coloring in the blooms.  We tend to set these aside as our showplants.  We’ve also found that many of these varieties tend to mottle more (in blooms and foliage) as the plants mature.

Crown Suckers

Question:  I’ve had problems with compound crowns in trailers, also occasionally a compound crown sucker in a miniature.  This occurs even in plants that haven’t been subjected to any unusual stress.  Also, leaves from these plants will produce offspring with this same habit.

Answer:  “Crown-suckers” can be very frustrating, particularly since they are difficult to remove without damaging the center of the plant.  As you noted, suckering is frequently induced by stressful conditions, since this is just another means of the plant trying to reproduce itself.  Showplants are notorious for suckering more when disbudded–preventing one means of reproduction only encourages another.  Any form of stress–heat, irregular watering, overuse of fertilizers or other chemicals, can induce suckering.

Sometimes, however, suckering occurs even under good cultural conditions.  Since this habit seems confined to a few varieties in particular, our guess is that this trait is genetic in nature.  Some varieties are just more prone to (crown) suckering than others.  As hybridizers, we also know that it’s a trait that is easily passed along in seedlings, and has to be “bred out”.  In other cases, this conditions is present in only a few particular plants (a “strain”) of the variety.  Acquiring a plant of this variety from another source (who doesn’t have this problem) would be the best solution.

Control of Fungus Gnats and Springtails

Question:  What pesticide do you use in your regular, preventative, spraying program?  I would like something to control fungus gnats and springtails in particular.

Answer:  Since we spend most or our days working amongst our plants, we try to use toxic chemicals as infrequently as possible.  In short, we don’t have a “preventative” program of spraying.  We do use them, but only when a specific problem makes it necessary.  Fortunately, we’ve never found pesticides to be needed to control fungus gnats or springtails.

Fungus gnats are those very tiny black flies that hover around your plants and in your lights.  They’re especially common in summertime, since they easily fly through window screens.  Springtails are very tiny, light-colored, thread-like pests that can be found on the surface of damp soil or in water saucers, and can “jump about”.  Neither are much of a threat to your plant’s health, unless found in very large numbers.

We’ve found that the simplest solution is to let the soil dry between waterings.  The plant needn’t go limp but, since both these pests desire moist conditions, eliminating the damp environment will eliminate the pest.  For those using wick or capillary-matting systems to water plants, let the reservoir/mat dry thoroughly before watering.  Also, these pests, like many others, feed on decaying organic matter–meaning dead or rotting leaves and blossoms.  Good culture and regular grooming can prevent a host of potential problems.

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