Gardening with Georgia

Archive - December 2013

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Of seedpods and seabirds

Wed, Dec 18, 2013 at 12:50:35 PM

An amazing number of seedpods on
this clump of Oeceoclades maculata
orchids growing in oak leaves.

Oeceoclades maculata, a terrestrial orchid found in shady forests along the northern Kwa-Zulu Natal coast of South Africa, made itself at home in Florida about 4 decades ago. It loves to appear in mulch, in leaf litter beneath oak trees and in shade. As I was cleaning up the garden for the holidays, I found a nice clump with more than 30 seedpods. It has steadily moved north from South Florida to Alachua County, even appearing in Tallahassee. Several individuals are scattered throughout my garden in mulched areas, especially loving the non-irrigated beds. Leaves are similar to sansevierias, and the flowers are small, greenish pink and cute. Listed as an invasive exotic, it doesn’t displace anything in my garden and so I allow it to flourish.

Last summer, I found a tiny bulb and decided to grow it in captivity. So far, so good. It is growing well in its 1-inch pot and has produces 3 more mini-bulbs. Checking on growing conditions, I discovered that it likes to be dry in the dry season, so I have moved it accordingly. I dropped a few pellets of slow-release fertilizer into the pot toward the end of summer, and will wait for spring to fertilize again.

Meanwhile, in a terrarium garden of miniature orchids,

Once known as Ixyophora viridisepala
this small orchid now is Chondrorhyncha

Chondrorhyncha viridisepala opened a single tubular flower, which at 1 3/8s inches, is a Gulliver among Lilliputians. The sepals of this South American orchid are horn-like and fleshy. Two sweep back and a third whooshes forward, so from certain angles it resembles a fat seabird trying to lift off the ocean. It is related to what was formerly called Cochleanthes amazonica, but now is Chondrorhycha amazonica, an orchid that is well known among South Florida orchid growers.

Dendrobiums and cattleyas continue to bloom now, and spikes are lengthening on Phalaenopsis schilleriana. All are loving the cool-ish weather that finally arrived Monday. As your phals put out spikes, try to keep them facing the same (southern) direction until they flower so the blooms will display an orderly beauty.

A reminder about bromeliad beds: look for the stray brown leaf, then (wearing long sleeves or elbow-length gloves) lift the leaves above them to see what’s going on. Lots of plants have matured and are dying now and require removal lest they take on the aroma of fish too out of water.












Orchid alert

Mon, Dec 02, 2013 at 10:31:09 AM

Over the past week, we have noticed some disturbing signs in our orchid houses. The phragmepidiums and paphiopedilums have more yellowing leaves than usual, and the cattleyas and even the phalaenopsis orchids have some scale. Oncidiums and some cattleyas bulbs are showing some brown, soft tissue at the base signifying rot. This is the result of the weather, which has been rainy and humid while the light has turned the corner and become less intense winter light.

Without good air circulation in these days of high humidity, rain and shorter days, orchids are susceptible to such poxes and pests.

Examine your orchids carefully and reduce your watering schedule. Look into the crevices between leaves for scale; look under leaves for scale when yellow spots appear on top of them. Watch for black rot at the base of pseudobulbs on cattleyas and oncidiums, and fungus (brown areas surrounded by a yellow halo) on all plants. Have cinnamon or alcohol at hand. If the ends of leaves turn brown, cut away the area and treat the cuts with a Captan paste. If you cut out rotting pseudobulbs, treat the remaining good tissue with Captan paste.

 In this month’s orchid newsletter, Martin Motes recommends using hydrogen peroxide on vandas and phalaenopsis with crown rot. Hydrogen peroxide comes in various strengths: 3%, 5%, 8% and 35%. Use 3 percent. You will see the bubbling characteristic of hydrogen peroxide. Treat daily until you see no more bubbles forming.

Edema, but not a disease.

(Hydrogen peroxide can be used as a spray to prevent fungal and bacterial disease. Spray it weekly on orchid leaves in the growing season or in weather such as we are experiencing now.)

Because the recent days have been hot, you may have forgotten to reduce the amount of water you are giving to your plants. Suddenly, cattleya and dendrobium leaves are showing black markings that scare you to death. It is edema, swelling of tissue caused by the plants receiving too much water. There is nothing you can do about it now; just cut back on the water. It's not a disease!