Cultivation – Page 4 – South Florida Orchid Society

Falling Leaves – Cattleyas

Caring

Oct 012009

by Susan Taylor
Originally published in BellaOnline

In general, leaf loss in Cattleya Alliance orchids is not considered to be a major growing problem. Unless you have very good growing conditions and have solved most of your cultural problems, you are going to lose the leaves on the older pseudobulbs of your Cattleyas. It is an exceptional grower who can keep these plants happy enough to produce a specimen plant. That is not to say that the hobby grower cannot do better to reduce leaf loss than the average grower. There are three main reasons for leaf loss: diseases/insects, culture and genetics.

In the diseases and insects category, scale is the main culprits. Scale is easy to spot once you have ever seen it – a grouping of white fuzzy spots. Left untreated scale will overtake a plant and ultimately will kill it. As soon as you see evidence of these pests, remove the plant to a location away from your other plants. Manually clean up any obvious insects or spray the whole plant with Bayer’s Rose and Flower Insect Spray (dual action) which will kill any pests that it touches as well as be absorbed in the plant and will kill adults as well as any sucking insects. Continue to spray for about 3 months.

Cultural practices which will cause leaf loss include overwatering, under-watering and excess cold and or heat. Overwatering will cause the roots on your plants to die off so they cannot support the plant. In an attempt to stay alive, the plant will shed extra leaves and try to keep the new growth alive. If possible, look at the roots of your plants – some growers actually take their plants out of the pots periodically to assess the growth. An old rule of thumb says that if the second oldest pseudobulb (generally from the previous year) is wrinkled and desiccated, you are either under or overwatering. Take your plant out of the pot to see which it is. If the roots are good and plump, then you’re under-watering. If they are all dead and rotten, you have overwatered. Repot and change your culture.

Another cultural practice which will cause leaf drop is very cold temperatures in the winter and very hot temperatures in the summer. Most Cattleya Alliance plants will withstand a wide range of temperatures, but very high and low temperatures, even within their range, will cause them to be stressed and lose leaves.

Genetics will also determine whether the plant will grow large for you or lose leaves once they are a couple of years old. There is little that can be done for this aspect but to determine through trial-and-error which plants are best for your growing conditions and stick to them.

One point to keep in mind is that if you can keep from doing it, it is much better to allow the leaf to drop off naturally than to cut it off. If the leaf will not snap off with light pressure, leave it on until it is ready to come off. The plant will seal the wound through a natural drying process which will keep any pests or disease from using the area to invade the plant.

Fall Orchid Growing Tips

Fall

Oct 012009

by Susan Taylor
Originally published in BellaOnline

Repot
Fall is a good time to repot those orchids which have already bloomed and are going into a rest period or growing pseudobulbs which will mature over the winter. With cooler weather the transplanting process will be easier to bear. Some of the varieties to repot are Doritis, Doritaneopsis and Encyclia as well as Phal seedlings.

Move Your Phals to a Cool Spot at Night
Fall is the time to move your Phals to a cool spot, around 60 degrees Fahrenheit or 15 Centigrade at night, until you see inflorescences starting at the base of the plant. When the growths are about 2 inch or 5 centimeters long, the plants can be moved back to their normal warmer conditions. Stake the inflorescence beginning at about 6 inches or 15 centimeters and make sure that you keep the plant positioned the same direction in relationship to the light for best presentation of flowers.

Move Plants Inside
Prepare all your plants for moving into warmer conditions before the first cold front arrives. Check them for insects in the pots, clean up dried out sheaths where bugs might hide and even start moving some of the tender plants inside as night time temperatures cool. Then you will ready for that first really cold weather and only have a few plants to take care of at the last minute.

Water and Fertilizer Requirements Change
Fall is a time when you will need to adjustyour watering and fertilizing schedules to accommodate the variable weather conditions. As the temperatures cool your plants will use less water and start slowing on their growth, so will need less fertilizer. Generally I keep with my same fertilizing schedule of every other watering throughout the year. But in fall that watering goes from twice a week to every five days and then to once a week in winter.

Keep Your Air Circulation Going
It is especially important during the fall and winter months to keep air circulation going especially in a greenhouse or enclosed growing space. Mold, mildew and insects thrive in stagnant conditions and will cause many problems without proper air circulation.

Light Requirements are Changing
Fall brings changes in light conditions for inside and outside growers. Make sure your plants are getting enough light with the changing conditions or move them around if you are removing shading used during the hot summer months. Leaves on orchids can burn if they get too much direct sunlight.

Could Tums Help Orchids Too?

Caring

Oct 012009

A couple of years ago, I asked Andy Easton why some of our Catts had black tipped leaves. He said might be a calcium deficiency. Since then I have added 5 Tums tablets to every 20 gallons of fertilize solution. I start softening the Tums several hours ahead of adding the fertilizer, 15 aspirin, and detergent to the mix. Our black tips are gone, and while the calcium is at best in suspension, the particles seem to some how get into the roots.

Dot Henley

Getting Orchids Ready For Fall/Winter

Fall, Winter

Sep 012009

by Liese

Even though it’s early September, fall seems to be in the air. The days are slowly getting shorter, the nights cooler, and some trees are even beginning to lose their leaves. The kids are back in school and our summer “routines” must change.

Most of us are creatures of habit. Watering our plants every Saturday morning and fertilizing once-a-month, whatever it may be. What one must remember is that as the seasons change, the climate conditions change, thus, the care of your orchids must also change.

Fall brings shorter days, cooler nights, and lower light intensities. These conditions are necessary to push many orchids into spike. However, the care we give them must change slightly to accommodate the new season. During the fall and winter months, the plant growth of orchids slows down and, in some cases, stops entirely until spring. Because of this, we usually cut back of our watering and fertilizing. It is good to switch foods to a blossom booster formula during the fall and winter. Blossom booster cuts back on the nitrogen and pumps up the phosphate, a combination that encourages blooming. With the lower light during these months the orchids simply do not use up as much food, so make sure to reduce your fertilizing frequency and/or switch to a blossom booster.

The plants also do not use up as much water during the fall/winter months. You will want to water your plants thoroughly as usual. However, due to the darker, cooler days, it may take longer for your plants to dry out. The best thing to do is to evaluate and change your orchid care as the seasons change. Be aware of the plant growth and moisture content. Don’t get caught up in too much of a “routine” of caring for your orchids. Learn to study the plant and decide on it’s specific needs for that week, month and season.

Spider Mites on Orchids

Pests

Aug 012009

by Susan Taylor
Originally published in BellaOnline

Spider mites are closely related to spiders. They are nearly microscopic in size and are not often suspected until the damage is visible, usually on thin leaved orchids such as Dendrobiums. The leaves will have a silvery look caused by the death of cells at the surface of the leaves due to the sucking of sap by the mites. This is most apparent on the undersides of leaves and sometimes it will look like there is dust or dirt on the top of the leaves.

Some spider mites spin a protective web which can cover the underside of leaves during a bad infestation. To verify that you have mites, spray the underside of the leaves with a fine water spray and then hold up to the light. The webs should be made visible from the spray. You may also be able to see the tiny bugs moving on the webs. These webs will keep any spray off the eggs and the adults if you do not destroy it manually.

They are particularly invasive during hot, dry weather and the life cycle only takes about a week during warm temperatures. Each female can lay three to five eggs per day and thus produce more than 100 eggs in about three weeks. It is very important to identify the problem early and take immediate action especially since you already have an infestation before you can see any signs of the problem. Keeping humidity in your growing environment is detrimental to mites since they prefer dry air. Hand washing of leaves or spraying with water will remove many of them from plants and kill them from the pressure of the water spray.

After you have determined that you have mites, it is very important to move quickly or they can kill you plant. Wipe the leaves on both sides with a damp cloth moistened with water and soap. This will destroy the webs and will manually kill the mites you touch. Then spray with a mixture of 409 Cleaner (one pint), rubbing alcohol (one pint) and water to make a gallon. Spray all surfaces of the plant as well as all surrounding plants. You will need to spray every fourth day for about a month to contain the infestation.

There are also chemical controls called miticides which can be used to control these pests, but most are not available to hobby growers. Horticultural oils such as Neem Oil will help control these pests, but their application during hot weather must be done carefully. Apply in the evening so that there is time for the oil to kill the pests without any direct sunlight on the plants.

Lubber Grasshoppers

Pests

Aug 012009

Lubber Grasshoppers by Susan Jones

One of the largest and slowest moving grasshoppers, lubbers can attain 3 inches (7.5 cm) in length at maturity, and cause a great deal of damage to an orchid collection. Different species are found in various geographic regions of the United States: eastern lubbers (Romalea guttata, found from central North Carolina west through southern Tennessee, Georgia, Alabama, Mississippi, Louisiana, Arkansas to Texas and throughout Florida), horse lubbers (Taeniopoda eques, native to Texas and Arizona, down into Mexico), plains lubbers (Brachystola magna, most commonly found on the prairies of the western part of the United States and Mexico) and southeastern lubbers (Romalea microptera, which spread out from North Carolina to Florida, west to Louisiana and northeast to Tennessee).

DESCRIPTION

Although there is some variation among the different species, all are flightless and quite large as grasshoppers go, with females attaining greater length at maturity than males. Distinctively colored and patterned, the immature ones have different coloration from their adult counterparts. All share the chitinous exoskeleton typical of grasshoppers that helps protect them from predators and prevent dehydration.

Eastern lubbers are flightless, although not wingless. They move from place to place primarily by walking, but are capable of jumping short distances. Adults of this species are yellow, spotted black, with red coloration under their wings, and reach 2⅜ (6 cm) to more than 3 inches (8 cm) in length.

Unlike some of their less athletic cousins, horse lubbers have long hind legs that allow them to cover distances of up to 20 times their own length in a single jump. These lubbers are black at maturity, with yellow markings and black-and-orange-striped antennae, and attain a length of 2½ inches (6.4 cm).

Flightless plains lubbers are also capable of jumping from several inches to several feet using their oversized hind legs. Their bodies are reddish brown in color, marked with greenish brown. Their wings are colored with ABOVE Southeastern lubber nymphs feeding on landscape foliage. reddish brown and black spots, and they have a row of light-colored dots on their abdomens. The smallest of the lubbers, this grasshopper is still fairly large, reaching up to 1⅝ inches (4 cm) in length as an adult.

Adult southeastern lubbers come in two color schemes: mustard yellow with black markings, the southerners among them with a reddish stripe as well, or black with yellow stripes. They grow to be 2–2¾ inches (5–7 cm) in length, and are flightless.

LIFE CYCLE

After mating, lubbers deposit caches of approximately 25 to 50 eggs, depending on the species, in the ground during the summer. These eggs overwinter underground and begin to hatch out from mid-March to June, depending on the region. In warmer areas, such as the southeastern United States, the hatching is earlier, while for species such as the plains lubbers in the western parts of the country, later spring is the expected arrival time for the young. The wingless nymphs (immature grasshoppers) crawl up out of the soil in groups and begin their search for food. The young lubbers will molt their exoskeletons five times at roughly 15-day intervals before reaching adulthood, when they settle down to breed and begin the cycle anew.

HABITAT AND FEEDING

Although each type of lubber has its preferred plant or plants on which it feeds in its natural environment, all are fairly catholic eaters and, given the opportunity, will usually cause damage to a wide variety of greenery. This includes one’s prized orchids. Young lubbers usually travel in large numbers, swarming and devouring plant material as they go. Knowing which plants they favor can help growers to be on the lookout for these pests; also, keep orchids far away from host plants. Eastern lubbers are most often found in open pinewoods, weedy fields and the vegetation along roadsides. Their preferred foods include the foliage of citrus, vegetables and ornamental plants. Horse lubbers stick to grasslands and oak woods, desert annuals and foliage of perennial shrubs, including mesquite. The plains lubbers hang out in the prairies, roadside vegetation, in vacant lots or at the edges of fields. Their favorite food is sunflowers, but they will also consume various grasses, weeds and many other types of flowers and young cotton plants. Southeastern lubbers frequent roadsides, field edges and gardens, noshing on ornamentals, vegetables and even citrus leaves.

DEFENSIVE CHARACTERISTICS

Lubbers have at their disposal a variety of relatively unpalatable means of defending themselves against threats from other creatures.
The bright coloration and patterning on a lubber’s shell is an aposematic, or warning, pattern to predators that they are unpalatable to downright poisonous. Lubbers ingest and assimilate substances in the plants they consume that, although harmless to humans and the lubbers themselves, are toxic to many predators. These chemicals may kill smaller creatures such as birds or leave larger animals quite ill after ingesting a lubber.

If their color pattern is insufficient to warn off a would-be predator, the lubbers are capable of secreting a noxious foam while making a loud hissing sound when threatened. In addition, like most grasshoppers, they can also regurgitate a dark brown liquid (commonly called tobacco spit) as a defense.

Lubber adults are colorful and formidable in appearance.

CONTROLS

Chemical control is effective only against the nymph stage. There are several insecticides toxic to grasshoppers that are registered for use on ornamentals, fruits and vegetables, such as Cygon. These are not, however, approved for use on orchids. If control of the young lubbers on host plants for which the insecticides are approved is the goal, chemical control is an option. Otherwise, these pests are best eradicated by hand. Because most species are fairly slow moving and all are harmless to humans, they can be handpicked from a favored plant or netted. Various orchid growers recommend their own preferred lubber-control weaponry, including a brick, shoe, broom or even the broad side of a machete, but squashing them does seem to be the favored approach.

Reprinted from the APRIL 2004 issue of Orchids — The Bulletin of the American Orchid Society. Copyright American Orchid Society — www.aos.org

Snails and Slugs on Orchids

Pests

Jul 012009

by Susan Taylor
Originally published in BellaOnline

Snails and slugs are a constant problem for outdoor and greenhouse growers of orchids. They love the open medium of bark used for orchids and can cause great damage to new growths of both roots and plant tops. Most of the time the first sign that there is trouble will be an almost ruined plant, they will invade that fast. It is important to get rid of these pests before bringing in plants for the winter.

The first suggestion, as always, is that prevention is the best solution to the problem. There are as many ideas on preventing the critters as there are people who battle them. One ex-military expert suggests a “perimeter defense, local defense and all out war” approach. Others advocate diatomaceous earth (DE), others various slug and snail pellets. My personal prevention regimen involves a monthly application of approximately a tablespoon DE to each pot; scattering a snail and insecticide inside on the floor of the greenhouse and outside the perimeter; and using the “beer in a container” catch approach. I personally can’t stand having to mess with the dead pests in the beer approach, but periodically I will do so just to get those that have escaped the other ways. Please note, never put slug or snail bait in your orchid pots, always put it around them on the ground.

Other recommended approaches are to use a .5 to 1 inch (3 centimeter) strip of copper around the bottom of all benches or approaches to the orchid location. This can also be used around the bottom of pots. The theory is that the snails and slugs will not cross the copper because it gives them a very slight shock which they dislike.

A recent test confirmed that spraying with a 1% caffeine solution (strong brewed coffee has about .5% caffeine) will kill 65-90% of snails present in potting medium without harming orchids. This can be done by spraying or by pour-through. Caffeine can also be purchased in purified form for agricultural use and mixed with water for this purpose.

In almost all instances a combined approach always works better than relying on just one preventative or poison. There will be some of the pests that will get past your defenses, but few will make it past two or three.

Snail and slug poisons vary by state, so you should consult with your local nursery to determine what is available in your area. As noted above, never put any of these products in your pots — many of the products can be toxic to orchids. Most of the products are granular and will attract the pests from the medium where they hide during the day. Be sure that you read all directions in relation to children and pets. If you chose to use the DE method, be sure to use a mask when applying so that you do not inhale any of the product. Beware of dogs and children who might inhale also.

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

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.

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