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 January has been warmer than average much to the delight of our orchids which have enjoyed day time temperatures hovering around 80 degrees and falling 15 degrees at night. These conditions mimic the mid-elevations of tropical mountains where many of our orchids originated. The swings of day to night temperature stimulate root growth in vandas and these should be feed to produce additional leaves each with its leaf axil harboring a potential flower spike. The higher temperatures require extra care for our sympodial orchids which are resting, avoid watering them when watering those vandas. Temperatures have remained cool enough to suppress Thrips but the air is dry enough to encourage mites. Raising humidity by wetting down growing area floors will discourage mites. The temperatures are suitable for an application of oil (1.5 oz. per gal) followed in 7-10 days by soap (2 oz per gal) which will eliminate mites and any scale crawlers which have emerged. On some of the warmer days relative humidity may be quite lower than expected and our vandas may require extra water but still only early in the day as the plants should not go to bed wet in the short days of winter.
Although the general trend has been warmer than average, the winter storms which are ravaging the north are occasionally punching their way down to us. Be prepared to protect the most cold sensitive plants while allowing those that relish the cold to do so. These differences between different orchids in cold tolerance are set forth clearly in Florida Orchid Growing. One law for the lion and the ox is oppression. Moving the wrong plants around can often cause more harm than good.
Meanwhile savor the beautiful weather which is why we live in one of the world's most delightful climates.
If you do have cold damaged plants, be sure to check out our advice on treating cold damaged plants by clicking below, but whatever you do:
Never, never apply chemical as a dust as the danger of inhaling them is far too great. We have more information on this topic on our website, which you can read by clicking here.
When weather turns nasty, knowledge of the cold sensitive of various genera outlined in Florida Orchid Growing (p.117-120) is essential to protecting our most vulnerable plants.
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