South Florida Orchid Society

Summer In South Florida

Summer

May 012009

By Andy Easton, V.P. Life Sciences, Kerry Bromeliads,
Homestead, FL

These are a few things, in no particular order, that you might wish to consider that could help your plants through what is often a very difficult growing season in South Florida.

It’s hot and the plants are growing like crazy so we need to fertilize more, right? Wrong! The two periods of most rapid growth in our area are Spring and Fall. When the days and nights get uncomfortably hot for us, they are too hot for many of our orchids too. The respiration rate will exceed the photosynthate storage rate for much of the 24 hour period and consequently, just like when we go on a diet and exercise more to lose weight, our plants will actually struggle to hold their own or may even go backwards. In the months of July, August and September, it is prudent to actually feed at a lower concentration and also to make sure you are feeding a formulation that is at least even concentrations of Nitrogen and Potassium and preferably with a Potassium level around 25% higher than Nitrogen. Don’t skip feeds however as the higher temperatures mean that fertilizer is quickly metabolized by media microflora. Now if you just grow Vandaceous types these comments are less applicable but anything in the Cattleya Alliance will benefit from the above regime.

Be sure too that you water and fertilize in the early or late hours, I personally prefer morning but the orchid leaf stomata are open at either time. It is not necessary to get into a debate about foliar feeding here but I am sure the elevated bacterial leaf presence in warmer months greatly assists in plant nutrition by converting fertilizer into gaseous ammonia which is then readily taken up through the leaf stomata. Research has shown that Phalaenopsis stomata are open at night but be careful watering them in the evening as crown rot will be a problem. People say to me that if Phalaenopsis can survive in their natural environment where it rains every day in Summer and often in the evening, why can’t they behave the same in cultivation? There are two main reasons why we run into problems with cultivated plants. Firstly. The plant orientation is all wrong. Phalaenopsis in nature develop so that the leaves drain water away from the crown. We place them in pots and all the water essentially runs backwards and accumulates in the crown, just where we don’t want it at nighttime. Secondly rainwater is a different “cat” to well or city water with added fertilizer and it is much less likely to support pathogen growth.

Plant disease researchers have found that elevated levels of certain nutritional elements like Magnesium will contribute to a plant’s ability to resist fungal and bacterial infection. Epsom Salts (Magnesium Sulfate) is a cheap and effective source of this critical plant nutritional element. Once a month in Summer, instead of watering and feeding, water and feed Epsom Salts. It doesn’t mix well will fertilizers so should be used on its own and even if you don’t have the capacity to liquid feed it, you can even apply it as a topdressing without any risk of injury to your plants. Feed at the rate of a level teaspoon per gallon or top-dress at the rate of a level teaspoon per six inch pot.

There are oils and oils. Some people have done major damage to their plants by using the wrong oil at the wrong time of day or year! But, the paraffinic oils like Ultra-Fine which can be purchased for around $11.00 a quart at Home Depot are wonderful for home growers. I spray all my plants in the greenhouse at home with Ultra-Fine every month, year round. You have no toxicity issues to worry about so you can spray in your swimsuit if you wish and these paraffinic oils will really keep mites, scale, thrips and mealy bug on the back foot. If your water is high in Calcium, they will also help keep your plant leaves shiny. I tend to spray in the early hours because it is more pleasant for me but even if the sun is higher in the sky, only the thinnest leaves and most sensitive plants would be likely to be affected, if at all. Caution: with any spray it is always better in terms of efficacy and for systemic uptake, to spray when the stomata are open, i.e. in the cooler hours.

Although summer is not the most pleasant time to be in your greenhouse, make some time each week to do a slow walkthrough. For people who hand water this is not a problem but if you have overhead watering capacity, don’t just water and run!

Things can go bad very quickly in the summer months and a small spot of bacterial infection can become a sorry mess in hours rather than days. Spacing plants and a good fan for night air movement is critical to the prevention of most fungal and bacterial problems. Never let your plant roots come within 18 inches of the soil. The ubiquitous Fusarium wilt fungus is just waiting to attack your prize orchid and it is essentially, incurable. Just a splash of water which hits the soil under your bench and then bounces up onto a healthy Vanda root can spell disaster. Whenever I see people placing plants on the ground for easy watering, I just shudder. It is one of the most dangerous and unhygienic practices for your orchid plants.

Good growing! Make it through summer and be ready for the pleasures of the Florida Fall with a group of robust and healthy orchids.

How Long to Bloom?

Buying

May 012009

Reprinted from The Fort Lauderdale Orchid Society

Joyce Kelly found this good information in a 1982 Jones & Scully catalog. Pot size in standard size plants can help you guess when the plants may bloom. This is part of that chart:

Pot Size…………Years ‘till Flowering
2”…………………. 3-3 ½
2 ½”……………… 2-2 ½
3”…………………. 1 ½ – 2
4”…………………. 1 – 1 ½
4 ½”……………… 6 months – 1 year
5”…………………. 6 months – 1 year
6”…………………. flowering size

A Short History of Orchids

Curiosity

Apr 232009

The orchid family is not only the largest but one of the most diverse plant flowering families in the world. The orchid was one of the first plants to evolve on earth, it was around in the time of the dinosaur, over 120 million years ago. Given the length of time they have been around it shouldn’t be surprising that there are over 35,000 species with hundreds of thousands of hybrids.

The most famous orchid in the world is the vanilla orchid (planifolia). Coca Cola is the largest customer of vanilla, they use the seed for flavoring. Madagascar is the world’s largest producer. Orchids are very beautiful plants and that is why so much time and care is put into growing them. Vanilla on the other hand is grown for its commercial value rather than for its appearance but it is labor intensive. The vanilla crop is the main source of income for many independent farmers in less developed countries.

World’s Tallest Orchid

Curiosity

Apr 012009

by Susan Taylor
Originally published in BellaOnline

The tallest freestanding orchid is Sobralia altissma from the high forests of Peru. It is reported to grow up to 44 feet or 13.5 meters high in optimum conditions. The bright reddish-purple flowers are up to 6 inches or 15 centimeters across and are displayed in spectacular groups of up to 8 flowers per stem.

World’s Worst Smeling Orchid

Curiosity

Apr 012009

by Susan Taylor
Originally published in BellaOnline

The worst smelling orchid is Bulbophyllum phalaenopsis. We picked this particular Bulbophyllum due to the sheer size of the plant and flower and
therefore the amount of scent it produces. Many other Bulbophyllums produce the same carrion scent as this one, but are much smaller.
Native to New Guinea, the pollinator is a fly which is attracted by the unpleasant odor. Last year, I found a live webcam of an opening
flower — the grower couldn’t stand the smell but wanted to see the flowers opening!

Orchid Growing Tips #15

Caring

Apr 012009

by Susan Taylor
Originally published in BellaOnline

Ground cinnamon paste for wounds

Use a paste made of ground cinnamon and a common household glue, such as Elmer’s, to cover and protect wounds on plants so that they will not become infected with fungi. This remedy is for badly damaged plants that you truly want to save after being damaged. The glue will form a protective barrier and the cinnamon acts as a fungicide.

All purpose cinnamon spray

Cinnamon can also be used in spray formula. Made a mixture of 30 ml of ground cinnamon with 500 ml of alcohol and mix it well. Allow the alcohol mix to steep overnight and then filter to remove the sediment. A coffee filter will do this admirably. Mix 250 ml of the resulting liquid with a liter of water and 10 ml of liquid detergent. Use this as a spray for insects as well as a fungicide.

Always follow the instructions on insecticides

Protect yourself and your plants when applying any kind of product. Some of these products are poisonous to humans or pets as well as to the pests you’re trying to kill. Be especially careful if there are children around and only apply when they are not going to be in the vicinity. It is a good idea to wear protective gloves such as the latex gloves for dishwashing while applying insecticides even if the directions don’t call for them.

Always throw away old potting materials

When repotting, always maintain a clear distinction between old and new potting materials. Throw away any old potting medium which may contain pests or eggs of pests. One good idea is to spread out old newspaper and fold up and dispose of old medium after it is removed as well as the top layers of paper. You will then have a good sterile environment to put the next plant on. Dip plants in insecticide as well as fungicide before repotting in clean medium and pots.

When you cannot spray plants

An interesting idea I came across the other day was instead of spraying plants, take a plant with insect problems and tie it up in a plastic bag with a new dog or cat flea collar. Leave unsealed in the shade for a day to kill
insects.

To get rid of fungus gnats

To get rid of those annoying little fungus gnats put one of those mosquito larvae killing wafers in water in a bucket. Use this water for your normal watering. The insecticide in the water will take care of the larvae of the
gnats which eat decaying matter in the medium.

Rotate Vandas and sympodials

In order to get your Vandas and Ascocendas to grow upward rather than to one side, rotate them a half turn once a month. This will encourage nice upright growth as well as give the inflorescence a nice presentation.

Color Coded Spray Bottles

Use different colored spray bottles for different kinds of sprays—one for plain water, one for fungicide, one for an insecticide, etc. Using different colors makes it more difficult to spray with the wrong thing. Most garden centers today offer different shape, size and color bottles.

How to Make an Orchid Tree

Caring

Mar 012009

An orchid tree is a variation on mounting orchids, except you’re putting many orchids on a branch or branches to give it a completely natural look. The concept can be used in those areas of the country where orchids can be grown outdoors most of the year, but must be protected from a few frosts during the winter months; or if you are lucky enough to have a large enough greenhouse, brought inside during the colder winter months. It would also work wonderfully under lights in an alcove or under stairs area that proves to be a difficult place to decorate.
To start out, you must select the base for your tree, or build a wire mesh and cover it with cork. Remember that if you’re going to be moving the structure it cannot be too heavy. And you will need to make sure that it will not topple over when planted. Generally a tripod arrangement will ensure enough stability.

Attach the larger plants to the bottom for aesthetic reasons and the smallest on the upper portions. Think of the size of the branches on a tree, the largest are at the bottom and the smallest at the top. This will also provide extra weight at the bottom to balance the weight of the structure.

When choosing plants, be sure to try to pick out plants that will require similar light, temperature and humidity conditions. Depending on how you place your orchid tree, some will obviously get more light than others. Be aware of this when you start arranging the plants you wish to mount. Another factor to consider is flowering times. Do you want all your plants flowering at the same time, or several flowering at the same time throughout the year? And of course, the most fun of all, how are you going to arrange the different colors on the tree?

If possible soak the structure overnight before adding plants, otherwise wet it thoroughly with a hose. Take your plants from their pots, clip off any dead or brown roots and clean up the plants by removing dead sheaths, and back bulbs. Position the plants around the tree and if you want tie them on with a string until you’re satisfied with the arrangement. Then mount as you would any orchid on a mount with sphagnum moss attached with fishing wire against the structure. Then tie on your plant being careful not to cut into the pseudobulbs or roots. I prefer putting a bit of sphagnum on top of the roots too to provide extra moisture to the plants during hot periods. Continue mounting until all your plants are situated as you want them.

Mist thoroughly and place in a humid shaded area for two weeks to a month in order to allow the plants to accustom themselves to their new home. Mist every other day and water as you would any other mounted plant. Gradually move into a sunnier area over the course of about a week as you would for any other orchid.

Ionopsis

Species

Mar 012009

by Susan Taylor
Originally published in BellaOnline

These cute little miniatures are found from Florida through Bolivia and most of the Caribbean Islands. There are currently about ten species listed and most of them are twig epiphytes or tree growing orchids which need higher light and very quick drying conditions. It is listed as endangered by the USDA so if you ever see one in the wild you are very lucky.

They are similar in growth habit to Tolumnia and need much the same conditions. In general they are warm to hot growing and need year round water and fertilizer to encourage blooming in late spring and during the summer months. As you could see from the pictures, this little plant will put on a spectacular show from a mature plant when well grown. Most people grow it mounted on tree fern or cork so that he flowers can be well displayed as the branched inflorescences fall with the weight of the flowers. As with others that grow in this manner, watch out for spider mites and scale insects as they can hide in the crevasse and can kill the plants quickly.

The three main species grown are Ionopsis utricularioides, Ionopsis satyrioide and Ionopsis paniculata. There is some disagreement as to whether the last is a synonym (or the same species) as utricularioides but the flowering habit is different enough that we’ll address them separately here.

The most spectacular, without doubt, is Ionopsis utricularioides . It can be found from Mexico through Central America and occasionally on the Caribbean Islands and in South Florida. The flowers range from white to dark purple depending upon the cultivar. The branched inflorescence can reach three feet (or approximately 90 centimeters) with a hundred flowers. They are generally grown on small mounts and needs somewhat more shade than the Tolumnias. They need very good air circulation and high humidity year round. Intermediate temperature conditions of 80-85 degrees Fahrenheit, or 26-29 Centigrade, are recommended with a cooling at night of approximately 15 degrees Fahrenheit, or 9.5 Centigrade. The flowers are considered to be long blooming and will provide you with a great show. This is a plant that can be grown in Wardian cases since it remains in the 6 inch or 15 centimeter size range.

Ionopsis satyrioide has a smaller and less spectacular flowering habit, but you can easily see where the name “Violet Orchid” came from when you see it flowering. The flower is generally white with pink or purple striping. Culture is similar to utricularioides.

Goodyera daibuzanensis

Species

Mar 012009

by Susan Taylor
Originally published in BellaOnline

Goodyera daibuzanensis is one of the popularly called Jewel Orchids known for their lovely foliage rather than for their flowers which are generally not very interesting, picture of flower. Terrarium enthusiasts use this and many other Jewel Orchid plants to add leaf color and variety to their generally plain green environments much as gardeners use outdoor plants for the same purpose.

Jewel orchids are distributed widely throughout Southeast Asia, North and South America, and Australia. They are generally terrestrial in nature, growing in leaf mold in forested areas. They are spreading plants so can be placed directly in medium in a terrarium and they will quickly spread to provide a great show. Many jewel orchids will grow when just one piece is broken off and placed in appropriate medium and these babies can be given to friends for them to enjoy.

The various sp species are found around the world, some even in the northern US where they are known to as “Rattlesnake Plantain.” Most species are native to India, Sri Lanka, Japan, Malaysia, and Indonesia.

Goodyera daibuzanensis is found only on Taiwan, where it is quite common in mountainous forests between 800 and 2,000 meters where it will receive a good deal of rain. It is one of the smallest of the Jewel Orchids, with leaves only 2 inches, or 5 centimeters, long. The leaves grow in a really pretty rosette fashion which shows the silver and green striping and mottling to advantage. The flower inflorescences will grow to 10 inches, or 25 centimeters, high with small white flowers which are presented with a spiral around the stem.

Grow this little orchid in a terrarium with high humidity among other similar plants. Provide good air circulation to combat the formation of mold or bacterial problems. They require low light conditions which make them very easy to maintain in a home environment. Too much light will bleach their leaves to dull colors and you will lose the lovely contrast and velvety texture for which these plants are so prized. Many terrarium growers will simply cut off any inflorescences since they are often too big for a small container and are not at all showy.

To learn more about growing in a terrarium, Growing Orchids in a Terrarium or Wardian Case. This is a form of growing that is becoming more and more popular today. An excellent source for Jewel Orchids is Hoosier Orchids.

The How and Why of Water

Caring

Mar 012009

By Ron McHatton
AOS Director of Education January 2009
Copyright 2008 American Orchid Society

More or chids are killed by incorrect watering than by any other reason. There are two separate components to proper watering; when and how. The vast majority of orchids grown by hobby growers are epiphytes, growing on trees above the ground where the light is more plentiful. These plants are adapted to having their roots exposed to light and air so in addition to water, orchid roots need air. The central core of an epiphytic orchid root is covered with a spongy material called velamen designed to store water. When this spongy material remains wet too long, the central core suffocates and begins to rot. Once the roots begin to rot, the plant can no longer take up water properly and a whole host of problems begin. At worst, root rot will spread upward into the rhizome and cause the death of the plant. In other cases, the loss of roots prevents the plant from absorbing sufficient water to maintain the plant in good condition and the leaves will take on a wrinkled appearance. Unfortunately, the symptoms of over-watering and under-watering are superficially similar and the tendency is to increase watering rather than inspect the roots. Overwatered roots will be brown and mushy while those on under-watered plants will be white or gray and obviously dry. Let’s look first at when to water.

When do I water?
Orchids should be watered just as they dry out. This rule applies to all orchids with slight variations depending on whether your plant has pseudobulbs (thickened stems that are designed to store water) or not. Orchids such as cattleyas and oncidiums should be allowed to just dry completely between waterings while orchids such as phalaenopsis and vandas that have no water storage organs should be watered just before dryness occurs. For vandas, this may mean daily watering during the warm summer months. Vandas and ascocendas that are properly
watered will have actively growing root tips at all times. If the root tips on your plants dry up and seal over, you are not watering often enough. There’s unfortunately no magic formula; i.e., water a plant in a 6” pot every 7 days and you’ll be trouble free. This is because your growing area is different from anyone else’s. Humidity, air movement, potting medium (type and age) and light levels all play a role. There are several ways to determine when a potted orchid is almost dry: 1) the surface of the potting mix will appear dry; 2) dry pots will feel lighter when lifted; 3) clay pots feel dry; 4) a wooden stake or skewer inserted into the potting mix will come out almost dry. If in doubt, a finger inserted into the potting mix is perhaps the best tool to determine the moisture content of the potting mix. It will cause no harm to the plant. And remember, fresh potting mix will always dry out faster than the old medium.

How do I water?
How to water is just as important to proper culture as when to water. When orchids are watered, they should be watered copiously. Water should be provided until it runs freely from the drainage holes. This serves several functions. First, thorough, copious watering is necessary to soak the potting medium. In addition, thorough watering helps to flush away the salts that naturally accumulate in the potting medium from the dissolved salts in our water supplies and the fertilizers applied for good growth. Also, this is your opportunity to examine how the potting mix behaves. If you cannot pour water rapidly through the pot, the potting mix is too dense and you run the risk of starving the roots for air. If you see finely divided material that looks like coffee grounds in the water coming from the drainage holes, your potting mix is breaking down and it’s time to repot into fresh medium. At a minimum, try to thoroughly water your plants at least once a month. Finally a couple of notes about mounted plants and those like vandas that are grown in baskets without additional potting medium. First, avoid dunking these plants in buckets of water. This practice very easily spreads diseases. If one plant has a disease, all those dunked in the same bucket of water will have been exposed as well. Also, two short waterings a few minutes apart are much more effective than one long watering. Once water runs off the plant, the roots will have absorbed essentially all they can at that time and excess water simply runs off to the ground. The proper technique is to water your plants and then a few minutes later water them again, always beginning with the first plant you watered. This allows time for the roots of the last plant watered to finish absorbing water before you wet them again. Roots that are completely saturated will be a solid color while those that are not will appear mottled.

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