Motes Notes - Florida Orchid Growing
Progress of the Season
October has been exceptionally wet. When the rainfall from Tropical Storm Philippe is added, this October likely will set records. The volume of rain and the late duration of the rainy season can cause problems for our orchids. The most perilous is black rot a quick spreading and potentially deadly disease. Black rot is caused by two pathogens: Pythium and Phytophthora. These are water molds and not fungi, hence fungicides such as Heritage (recently recommended on a website) are ineffective in controlling it.
Two chemicals do provide nearly complete control of black rot: Alliette and Subdue. Both are systemic and curative. Alliette is the recommended choice for home owners as it comes in a convenient size package as wettable powder that is easily measured (2Tbs per gallon) and will keep for years. Subdue comes only in a size that will make 1600 gals of spray (1/8 tsp in 3 gals). Most hobby growers have difficulty measuring this and easily overdo. Truban an older chemical, while not as effective as Alliette or Subdue comes in a user-friendly combination with Thiophanate methyl as Banrot. Banrot applied consistently through the growing season provides protection from black rot and most leaf spotting fungi. As with most else, observation and the quick detection of infected plants is essential. Isolating infected plants in a dry location will prevent them from further infecting other plants.
At this point in this season every effort should be made to dry our plants as quickly and thoroughly as possible. Hurricane Irma has thinned our tree canopies quite well. Finding the brightest spots for our orchids short of burning them is our mission. Withhold water entirely from those genera such as Catasetum and dendrobiums from sections Dendrobium and Callista which are entering dormancy even though some may have broken into new growth with the extended rainy season. Better to allow those offseason growths to mature a little smaller than risk them rotting off. For other genera, be sure that they really need water before watering them. Remember days are much shorter now and watering early in the day is de rigueur.
Now is the time to think of protecting our more sensitive plants from the cold. Consult Florida Orchid Growing if you are uncertain of the cold tolerance of a particular plant. In general, it is wise to think of protecting all of our collection from northwest winds which will be blowing out of the cold heart of the peninsula. Installing plastic film on the north and west sides of the shade house or patio/ pool enclosure will always be worth the effort. Re-arranging plants to more protected spots is also wise but be aware that the sun is at a lower angle of incidence but is still strong enough to burn acclimatized plants.
January in Your Orchid Collection
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
February in Your Orchid Collection
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
March in Your Orchid Collection
Signs of spring abound with an abundance of emerging flower spikes and buds. The flush of spring growth will follow soon so plan your repotting program which should begin in earnest this month. The best time to repot is right before the new roots start growing so the plants will reestablish quickly. Watch for signs of mites, particularly on thin leaved orchids like the catasetinae and grammatophyllums, and treat any problems promptly...continue reading
April in Your Orchid Collection
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 in Your Orchid Collection
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 in Your Orchid Collection
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
July in Your Orchid Collection
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
August in Your Orchid Collection
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 in Your Orchid Collection
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 in Your Orchid Collection
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... read entire article
November in Your Orchid Collection
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 in Your Orchid Collection
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
by Dr. Martin Motes, from his monthly newsletter and book Florida Orchid Growing.
Monthly advice for orchid growers in South Florida. There's lots of information pertinent to North Florida growers too. Subscribe
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