April 2015 in y our orchid collection
brought to you by Motes Orchids
    Dendrobium lindleyii


March, which is going out like a lion up north, is certainly exiting a lamb here in South Florida. The unseasonable cold which posed a problem for only the most cold sensitive of orchids, the hard cane dendrobiums, should provide a bonanza of bloom spikes for our vandas which have been vegetating sulkily in the too-even temperature of this most delightful winter.


Mother's Day should be awash  in Vanda blooms if we protect those emerging flower spikes from the newly invigorated Thrips population which is exploding in our lawns and landscapes. This is the time of year when the most frequently asked question is, "Why do my Vanda spikes get about one inch long and stop growing?". Another FAQ of the season is, "Why do only half the flowers on my Vanda spikes open and the others fall off?" The answer to these questions, and more, is Thrips. Thrips are, in spring above all, public enemy number one. Spraying for them as recommended in  Florida Orchid Growing  is indispensable at this season. Flowers are not the most important thing, they are the only thing!


The delightful weather for much of March has given our plants, which are emerging from dormancy , an early start on what could be a fantastic growing season. Remember to fertilize plants that are commencing growth with low phosphorus liquid fertilizer. The late last cold will also serve as a diagnostic test of whether our plants are receiving enough magnesium. Any plants showing reddening of foliage should be treated to an extra dose of Epsom salts (1Tbs per gal). This is best applied together with 1 Tbs. of Potassium nitrate available from the suppliers listed in Florida Orchid Growing pg. 183-184.


Now is also a great time to apply time release fertilizer in a six-month formula. Be sure to use the gray stuff marketed at Lowes and Home Depot as Dynamite. It's easily applied (about one tsp per 6" pot) and can also be applied to mounted plants using carpenter's glue. Lowes has a low phosphorus formula for "Palms and Citrus" which is ideal.


Water very heavily when you water and benefit from the greenhouse-like drought of Florida spring.

Mornings will be delicious for another month or more. Get up early to enjoy the best Goldilocks weather of the year!


Martin Motes

President, Motes Orchids


Full speed ahead with re-potting
Water heavily and well
Don't forget to fertilize
Spray for mites and thrips



APRIL 4, 11am: FREE class at Motes Orchids: Growing Vandas  

Motes Orchids / 25000 SW 162 Av / Redland 

Contact Dr. Motes: martin.motes@gmail.com

APRIL 4-5: Flamingo Gardens Show  

3750 Flamingo Rd / Davie  

Contact Jan Amador: jamador@bellsouth.net

APRIL 11-12: Central Florida Orchid Society Show

Bahia Shrine / 2300 Pembrook Dr / Orlando 

Contact Joselito Tolentino: macykulit@aol.com

APRIL 11-12: Tallahassee Orchid Society Show

Bldg. 3125 Doyle Conner Blvd / Tallahassee 

Contact Carlos Fernandez: cfwebproductions@aol.com

APRIL 19, noon: Florida Caribbean Judging Center

Monthly AOS Judging / Fairchild Tropical Botanic Garden

10900 Old Cutler Rd / Coral Gables

APRIL 25-26: Vero Beach Orchid Society Show

Riverside Park / 3001 Riverside Park Dr / Vero Beach 

Contact Doug Mews: instedof@bellsouth.net 



Average high: 83.8

Average low: 67.6

Average mean: 75.7

Average rainfall: 3.36"


Far from the cruelest, April is the kindest month to South Florida orchid growers. The weather in April is definitely settled into warm, even deliciously hot, with passing cold fronts only adding the delight of a pleasant change in temperature. The clean, bright days brimming with abundant sunlight and the low relative humidity create the high drying potential that orchids love. Now we can get our orchids off to a great start on the growing season by practicing our very best watering skills under ideal conditions. Water heavily when you water and allow the plants to dry thoroughly before watering heavily again. Drying 'hard' in the spring will produce benefits all season. We want to get our plants well launched while leaving all the fungi high and dry.


The new shoots of Oncidinae, grammatophyllums and dendrobiums forming now are quite cup-like; care must be taken that water does not stand too long in these immature growths. Water these types very thoroughly with two or three applications of water spaced 10-15 minutes apart. Water should run freely through the pot on each application. Saturated thoroughly in this fashion the plants will need only weekly watering. Even more care should be taken with the soft plicate leafed genera like Catasetum, Mormodes, Cycnoches, Gongora, Calanthe and Thunia The new growths of this type are rolled together (the fancy word is convolute) like a collapsible drinking cup. These should be grown in water retentive media that should be saturated at each watering to permit the developing roots to have abundant water but allow the vulnerable new growth extra time to dry. Feel the weight of a pot when you have finished watering. Be sure it is heavy with water. If it's not, water one more time. With plants properly spaced, good drying should not be difficult in the hot dry air of April. But do be careful to water early enough in the day to allow the tender new growth to thoroughly dry by twilight.


With vandaceous orchids grown in slatted baskets, most growers find that they dry altogether too well in April. Vandas can be watered almost every morning in April. Indeed, a second light watering or misting in mid-afternoon in April and early May is often beneficial provided the crowns and leaf axils of the plants have time to dry completely by nightfall. Another strategy under high drying conditions is to bend the rules, at least occasionally, and water heavily in mid to late morning. Late waterings on weekend mornings (you didn't want to get up early, any way) provide relief for plants that are more stressed on week days with their owners absent. Very occasionally, one needs to break the rules absolutely and water thoroughly (not just mist) in the mid to late afternoon so the plants can slowly absorb the water across the cool hours of the night. This is the season that one must be sure that Vanda roots have turned overall dark green when we have finished watering. Two applications of water to the point of runoff spaced several minutes apart should accomplish the required color change from white to totally green. Saturated roots are absolutely necessary to provide the plants the moisture the plants need to withstand the heat and dry air typical of April. Sometimes, particularly at this season, the roots will not change color even after the second or third application of water. This lack of response to water is because the roots have become so dry that they are repelling rather than absorbing water. They are behaving like a cork in a wine bottle. The grower must exert special effort to re-saturate the roots. Often this will require 4 or 5 waterings to the point of run off spaced 15 minutes apart. Once the roots have been changed to the healthy overall green, normal applications of water should bring them around in future.


With increased heat and light and the onset of growth, fertilizer becomes more crucially important to the plants. Balanced time release pellets (13-13-13) can still be applied to potted plants provided the duration is 180 days or less. Most time release fertilizer breaks down faster under South Florida conditions and should be exhausted by October when we will want our plants to slow down. The brand marketed at retail as "Dynamite" is generally considered by professionals as superior in reliability to other types. In April, 15-5-15 can be applied to most genera at the rate of 2 tsp. per gal every two weeks. Vandas, ascocendas, Aerides, et al will benefit from a full tablespoon of 15-5-15 weekly during this high energy period. One can also apply high phosphorous 'Bloom Booster' fertilizer once or twice at this time to stimulate them to flower for Mothers' Day or failing that to win those trophies and AOS awards at the Redland International Orchid Festival the next weekend. High phosphorous (we use Millers' Solugrow 8-48-12) also stimulates root action and is important in getting all genera off to a good start on the growing season. This is one of the few times that high phosphorus is perhaps beneficial. During the rest of the year it is to be avoided particularly with our alkaline water. Current science recommends fertilizers lower in nitrogen, much lower in phosphorus and higher in potassium, magnesium and calcium. Peter's Excel 15-5-15 is now the standard for year round use.


The warmth of April, alas, stimulates the growth of bugs as well as plants. Both Thrips and mites thrive in the dry heat of April. Liquid dishwashing soap (at 2 oz per gal) will control both but be mindful that soap should not be applied to plants that are suffering from drought stress. Be sure that your plants are well hydrated before you apply soap. Water them extra hard the day before. To be effective soap must be used profusely. The plants should be washed in the solution to the point of wetting every nook and cranny of both the plant and its container. Only such thorough treatment can reach the reclusive Thrips and be sure to touch all of the ever prolific mites. A second treatment at 7-10 days is necessary to control mites and a miticide such as Kelthane might be advised. Orthene which is the insecticide of choice for Thrips (because of its residual action) is compatible with many miticides. Check with your county agent if in doubt.


April is the classic month to catch up with all the re-potting which you meant to do across the winter. New roots form fast in April; don't rot them off by over-potting or break them off by allowing the plant to wiggle in the pot. Tie them up: tie them down!


April is a month for great moral decisions. When turning on the air conditioner for the first time, consider how much better an orchid grower you would be if you set the thermostat 2 or 3 degrees higher. You will find that you spend more time with your plants when you are accustomed to slightly higher temperatures and it is the master's shadow that makes the plants grow. Besides spending more time enjoying your orchids, when the FPL bill arrives, you can celebrate with some splendid additions to your collection.


April is a great month for naturalizing orchids in the garden. Perhaps it's time to think of new homes for some of our burgeoning collection on trees or elsewhere. The space emptied in the growing area will soon fill with the healthy new growth of those plants which remain to enjoy their additional light and air.


  Dr. Motes brings over 50 years of experience growing orchids to bear on the problems confronting Florida orchid growers.
The follow-up volume that provides even more information about 
Dr. Motes' favorite topic: Vandas!

Mary Motes'  comic novel: a hilarious romp through an imagined world of orchids very similar to our own.

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