Orchid Culture - Motes Notes
Monthly advice for orchid growers in South Florida. There's lots of information pertinent to North Florida growers too. Subscribe to the monthly newsletter so it will be delivered to you via email each month.
by Dr. Martin Motes, from his monthly newsletter and book Florida Orchid Growing
Progress of the Season
This April has been cooler and much drier than usual with very wide swings of day to night temperatures. These conditions closely compare to the climates of tropical mountains where most of our cultivated orchids have their origins. With wide swings of temperature our plants are stimulated to produce an abundance of flowers and roots. Vandas have thrown an abundance of roots in response to these temperature shifts. It is essential that they receive sufficient water to sustain the growing roots. With temperature in the upper eighties and relative humidity in the 50% range Vanda roots can dry exceptionally quickly. This is the time of the year when an afternoon misting of Vanda roots is of great benefit. Even a second thorough watering on alternate days is beneficial if the plants are dry by night. Getting the vandas off to a quick start also involves heavy feeding. With the abundance of water being given, fertilizer at as high a rate as 1 Tbs. per gal can be given every 5-6 days.
Sympodial orchids are also enjoying the dry conditions. Their new growths are still at the base of the plant and are particularly vulnerable to prolonged moisture. They, too, need more water than has been falling from the sky but be sure to give it to them in heavy applications which saturate their roots and whatever substratum they are growing in. Typically, at this time of year, three passes of water from a breaker headed hose spaced in time by a few minutes is required to achieve the desired saturation of plants and media that have thoroughly dried. Liquid fertilizer should be substituted for the water every 7-10 days.
Although temperature have been a bit cooler, they have been sufficiently warm enough that Thrips have found our well-watered collections an oasis in the desert of our lawns. Watch for the first signs of Thrips in the pitting at the base of root tips. Although soap is a safe and useful control for Thrips, at this time of year care should be taken not to apply soap to plants which are suffering from drought stress. Be sure to water thoroughly in the morning and then apply the soap in the afternoon. Several other methods of controlling Thrips are to be found in Florida Vanda Growing.
Mites, too, are relishing the dry air and will pose a threat until the rainy season raises humidity to a level that dampens their ardor and the heavy rains wash them away. Soap also, with the same caution can be used to control mites but a second application in 7-10 days is required to achieve definite control.
Snails are in hiding during these dry conditions but following days when a second application of water has been applied are sometime induced to break their estivation. A light application of snail bait provides them a treat which will put them to sleep for good.
May is shaping up to be a little cooler than usual provide delightful weather to spend time at home with our orchids.
I am writing a new edition of Florida Orchid Growing. This updated edition will include up to date nomenclature and updated information on growing. Orchid societies can pre-order this book at a discount now. Email us with the number of cases you would like to reserve at the discounted price. Do you have feedback on the previous edition of the book? Questions you would like to see answered in the new edition? Now is your chance. Email us and let us know your questions and suggestions. Thank you.
January is somewhat like December but in reverse, with each succeeding day bringing longer hours of sunlight until days are long enough that afternoons return at the end of the month with extra sunshine to warm us after the extra sharp cold snaps. January, like December, is cold and dry, in fact even colder and drier. Dry is good, cold can be very bad. We need to accentuate the positive by especially... read entire article
Despite the bloom on the avocados and the burgeoning new leaves on the live oaks, February is not spring in South Florida. Danger of freeze continues past mid month and frost can occur still into March. Even if the weather is balmy, it's too early to let down our guard or take down any protection we have mounted against the cold. The trend however is toward the positive as each lengthening day brings extra hours of warming sunshine... read entire article
Whilst March never comes in like a lion in South Florida, occasionally it slinks in like a bob cat. Frost is not unheard of in the first few days of the month. The more cold sensitive genera, hard cane dendrobiums, phalaenopsis and vandas may well need some protection even into the middle of the month. Overall, however, March brings us some of the most ideal orchid growing conditions... read entire article
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... read entire article
May is a month of transition in South Florida. Early in the month we can expect the driest weather of the year. Because of the clarity of the air and lack of cloud cover, temperatures rise rapidly in the late morning and can reach the upper eighties or nineties by mid afternoon before cooling substantially in late afternoon. Fortunately, over night radiant cooling rapidly dissipates the previous day's... read entire article
June is the most dramatically tropical month in South Florida. As the southeast Trade Winds blow cool moist air off the Gulf Stream daily, as surely the heating effect of the center of the peninsula percolates up massive thunder heads. The increased cloud cover drawing a veil across the afternoon sun provides much cooling relief for our plants... read entire article
Although it mostly passes unnoticed to millions locked in their air-conditioned bubbles, July in South Florida is quite different from June. While the pattern of afternoon showers built from the moisture of the morning's sea breeze persists in July, the thunder-storms are sharper and shorter. The clouds linger less and the foliage dries more quickly. Less quantity of rain falls in July than in June... read entire article
July and August are the two most similar months in South Florida. Most of the advice on watering, disease and pest control in last month's calendar still apply but subtle changes are taking place. Although it may not seem so, as temperatures climb into the low nineties most afternoons, summer is in retreat: each day a little shorter, each night a little longer. With shorter days the importance of watering as early... read entire article
September looms as the only truly dismal month in South Florida. Even without the prospect of the unspeakable 'H' word, September disheartens since it is easily the dampest, dullest month in the year. Although more inches of rain fall in June, more hours of rain occur in the often slow, seemingly endless drizzles of September. Frequently a day or two can pass without so much as a solid hour of truly bright... read entire article
October is a month of change in South Florida. If the Romans had lived here where
we do, they would have named this month for their two faced god Janus. Usually
around the middle of the month, and certainly by the end of the month, the first strong
cold front pushes into South Florida bringing to a close the monolithic heat and damp
of summer and ushering in weather as most of the continent knows it, alternating
periods of warmer and cooler... continue reading
In November we can no longer afford to be dominated by the illusion, so easy here at the northern edge of the tropics, that summer will never end. Although Indian Summer persists for the whole winter in South Florida, November is the month to prepare our plants for those short sharp blasts of cold which are inevitably coming as each successive cold front pushes the overall temperature a little lower... read entire article
December marks the beginning of the serious dry season in South Florida. While this additional dryness provides relief from the autumnal rains that can bring so many fungal problems, December is also the month of shortest day lengths. This contracted period of light, on the contrary, reduces severely the drying potential for our plants. Nature thus both gives and takes away from us in December. We must... read entire article