Orchids and Their Care
The following is information gleaned from a Presentation by Palmer Orchids
(Any errors are attributed to Gardeners Out East)
The following is an overview of the most popular and readily available orchid genera going from those needing the most light [i.e., they grow high in the canopy in their natural environment] down to those needing the least amount of light [i.e., they grow lower in the canopy] and their general cultural needs.
Notes:
-Most orchids are from the cloud forest where temperatures range 54-72 degrees with constant humidity.
-Remove a plant from its natural environment and you are forced to try to re-create those conditions in the new, hostile environment.
-All orchid hybrids are registered with the Royal Orchid Society.
-Orchids covered in this presentation are epiphytes.
AIR MOVEMENT IS ESSENTIAL FOR ALL ORCHIDS that are epiphytes and grow on trees.
-Repot orchids when the orchid is putting out new growth – not when it is flowering. When flowering, most types of orchids do not put out new growth.
-Many orchids have green-tipped roots. The green tip is the growth plate – if this is damaged, you lose the root.
-When mounting orchids, be sure they are absolutely tight (no sphagnum between orchid and mounting surface). Water daily for 6-8 weeks until well rooted.
VANDAS and their related genera require extremely bright light in order to flower well. Some can be slowly acclimated to full sun conditions over time. ---Terete Vandas require full sun in order to bloom well. Being that these plants are mostly grown bare root in high light conditions, they need to be watered daily and in the extreme temps of the summer growing season twice daily.
Notes:
-If you must pot Vandas, use just pots (no sphagnum or bark medium) or wire.
-If Vandas experience temperatures below 65 degrees F, they may lose some of their lower leaves but will not die unless it’s REALLY cold. Plan to cover Vandas if temperatures are forecasted to drop to 39 degrees F.
-If Vandas are cold damaged, they will lose leaves. As soon as 4 or 5 roots at the top come out, cut off the rest of the roots.
-Roots are covered with velamen which acts as a sponge to hold water. If watered enough, roots are lime green. When temperatures are in the high 90s, plan to water twice a day: once in the morning and once in the afternoon (so that plants are dry by sunset).
-You may wish to apply fungicide once per month to prevent fungus which is caused by no air movement, draft or overnight wetness.
-Species Vandas bloom once per year; hybrid Vandas bloom more than once per year. Vandas bloom season is April through January.
DENDROBIUMS – the Antelope type Dendrobiums can easily be acclimated to full sun conditions. The normal Hard Cane Dendrobiums like light almost as bright as the Vandas. They like to grow in smaller clay pots, relative to their size, in a loose, open media that allows them to dry out quickly.
Notes:
-Hard Cane Dendrobiums are one step down from Vandas in the jungle canopy and they still need bright light. They hold leaves for just two years. They bloom on both and new growth. Old growth can die or get mushy.
-Hard Cane Dendrobiums like to dry out between watering. The small pot (i.e., the pot is small relative to the size of the Dendrobium) helps the plant to dry out faster. The growing medium must dry out within a couple of days.
CATTLEYAS require the same light as Dendrobiums and should be grown in clay pots in an open media and be allowed to completely dry out between waterings. They may also be grown in baskets or mounted on wood or trees. If they are mounted, they will need to be watered on a daily basis during the growing season.
Notes:
-Cats like the same exact conditions as Hard Cane Dendrobiums. Cats bloom from the top of the plant. A sheath forms to protect the flower (e.g., from predatory bugs) and to support the flower. Once the flower emerges, you can remove the sheath. Plants with sheaths tend to get fungus and scale insects under the sheath. [Scale insects will suck on dormant eyes.] To remove the sheath, blast it with the hose. Once it is wet, it slides off easily.
-Remove all roots outside the pot and all old roots when re-potting.
-Cats bloom only on new growth.
-Cats may be unifoliate (one leaf per stem) or bifoliate (two leaves per stem), depending on species. Bifoliate cats only put out roots once per year – don’t cut the roots. Bifoliates do not like “wet feet.”
ONCIDIUMS take less light than Cattleyas, what I would call extremely bright shade. Grow these in plastic pots in an open media that will retain a bit more moisture. They do not like to go dry for long periods of time between waterings. If the leaves of the new growth are growing out pleated, you are not giving them enough water.
Notes:
-Oncidiums grow midway down the canopy in about 50% shade (i.e., shade that is half way between bright light and dense shade). They have pseudo bulbs—plump dry roots outside the pot.
-They like to stay moist. A media containing sphagnum is a good choice. Loose sphagnum holds 10 times the water compared to sphagnum that is tightly packed so sphagnum can provide a variety of moisture levels.
-Roots die off from age. Roots outside the pot are typically drying – remove from the plant before repotting.
PAPHIOPEDILUM [lady slippers] (multifloral, strapped leaves) will take light at about the same level of the Cattleyas while the (mottled leaved) Maudiae type require a bit less light almost as bright as the Oncidiums. Both types require the same care. Grow them in plastic pots in an open media that retains moisture. They do not want to dry out between waterings.
Notes:
-Roots are brown and hairy (silica that take in water) and want to stay moist all the time. The pale green leaf (strap leaf) requires more light than the mottled leaf type of lady slipper. Otherwise, the care is the same as for the mottled leaf.
-Phragmipedium are similar to paphiopedilum but with sequential blooming. They like a small amount of standing water but still need to be watered from the top.
PHALAENOPSIS are probably the most popular and well known of the orchid genera and are shade growing plants. They grow in shady conditions on the lower limbs of trees in the jungle and like to be slightly damp at all times.
Notes:
-Shade is about 60% (i.e., shade that is more than half way between bright light and dense shade).
-Keep roots moist (not wet) all the time.
-When watering, let the water run through the pot. Make sure the sphagnum growing medium is moist throughout.
-Limp leaves mean too much water or too little water. Check the roots: if rotting, then too much water.
-On the flower spike, once all flowers have dropped, cut above the third eye from the bottom of the spike. This should promote a side shoot that will flower, albeit with fewer, smaller flowers. Only do this once per flower spike per year. Do not try to keep the orchid continuously blooming: the plant needs time to grow and constant blooming requires too much energy from the orchid.
-Phalaenopsis will not grow when it is in flower.
-This is a great “beginner” orchid. Most of the phalaenopsis sold in the US are Asian hybrids. China has at least one mile-long mechanized nursery specializing in Phalaenopsis. Orchid seeds have no exoderm – must germinate in sterile conditions.
-Phalaenopsis require a 15 to 20 degree drop in temperature overnight in the fall to trigger blooms. Overnight temperatures between 50 and 60 degrees for two weeks initiate new bloom here in Central Florida.
All the above-mentioned genera should be fertilized on a regular basis – what is commonly referred to as “weekly, weakly”. A small amount of fertilizer every week during the growing season (i.e., when not flowering). During our rainy season, I highly recommend a monthly treatment of both a topical and systemic fungicide to help prevent fungal infections that are to be expected when plants are too wet for too long.
Notes:
Pests, diseases and mechanical damage:
-Black areas with a yellow line or mushy black areas are actively growing fungal infections: cut ½ inch below the fungus and treat with cinnamon (a desiccant and a natural antifungal) or antibiotic gel (petroleum jelly) to create a water barrier.
-Black areas without a yellow line are fungal infections that the plant has taken care of. Do not treat these areas.
-If really cold weather is forecasted, do not water orchids. They do better in cold weather when they are drier.
-Washing leaves: photosynthesis occurs on the bottom side of the leaf so dust is not the same problem for orchids as for other plants. If you DO need to wash the leaves, use fresh cut lemons or whole milk to dissolve mineral deposits and remove dust.
-Periodically flush orchid pots to remove fertilizer (salt) build up.
-The presenter likes to use insecticides whose Mode of Action is growth regulator (e.g, Knack for Orchids).
-Fertilizer should contain Calcium and Magnesium as well as trace elements.
-BE CONSISTENT – if fertilizing once a week, always fertilize once a week. Orchids suffer otherwise.
-You can chop sphagnum and add it to bark – the compaction of the chopped pieces will determine how much water the sphagnum can hold. Hard bits hold less water than loose bits.
-Pot to root size – orchids like crowded roots.
Notes:
-Most orchids are from the cloud forest where temperatures range 54-72 degrees with constant humidity.
-Remove a plant from its natural environment and you are forced to try to re-create those conditions in the new, hostile environment.
-All orchid hybrids are registered with the Royal Orchid Society.
-Orchids covered in this presentation are epiphytes.
AIR MOVEMENT IS ESSENTIAL FOR ALL ORCHIDS that are epiphytes and grow on trees.
-Repot orchids when the orchid is putting out new growth – not when it is flowering. When flowering, most types of orchids do not put out new growth.
-Many orchids have green-tipped roots. The green tip is the growth plate – if this is damaged, you lose the root.
-When mounting orchids, be sure they are absolutely tight (no sphagnum between orchid and mounting surface). Water daily for 6-8 weeks until well rooted.
VANDAS and their related genera require extremely bright light in order to flower well. Some can be slowly acclimated to full sun conditions over time. ---Terete Vandas require full sun in order to bloom well. Being that these plants are mostly grown bare root in high light conditions, they need to be watered daily and in the extreme temps of the summer growing season twice daily.
Notes:
-If you must pot Vandas, use just pots (no sphagnum or bark medium) or wire.
-If Vandas experience temperatures below 65 degrees F, they may lose some of their lower leaves but will not die unless it’s REALLY cold. Plan to cover Vandas if temperatures are forecasted to drop to 39 degrees F.
-If Vandas are cold damaged, they will lose leaves. As soon as 4 or 5 roots at the top come out, cut off the rest of the roots.
-Roots are covered with velamen which acts as a sponge to hold water. If watered enough, roots are lime green. When temperatures are in the high 90s, plan to water twice a day: once in the morning and once in the afternoon (so that plants are dry by sunset).
-You may wish to apply fungicide once per month to prevent fungus which is caused by no air movement, draft or overnight wetness.
-Species Vandas bloom once per year; hybrid Vandas bloom more than once per year. Vandas bloom season is April through January.
DENDROBIUMS – the Antelope type Dendrobiums can easily be acclimated to full sun conditions. The normal Hard Cane Dendrobiums like light almost as bright as the Vandas. They like to grow in smaller clay pots, relative to their size, in a loose, open media that allows them to dry out quickly.
Notes:
-Hard Cane Dendrobiums are one step down from Vandas in the jungle canopy and they still need bright light. They hold leaves for just two years. They bloom on both and new growth. Old growth can die or get mushy.
-Hard Cane Dendrobiums like to dry out between watering. The small pot (i.e., the pot is small relative to the size of the Dendrobium) helps the plant to dry out faster. The growing medium must dry out within a couple of days.
CATTLEYAS require the same light as Dendrobiums and should be grown in clay pots in an open media and be allowed to completely dry out between waterings. They may also be grown in baskets or mounted on wood or trees. If they are mounted, they will need to be watered on a daily basis during the growing season.
Notes:
-Cats like the same exact conditions as Hard Cane Dendrobiums. Cats bloom from the top of the plant. A sheath forms to protect the flower (e.g., from predatory bugs) and to support the flower. Once the flower emerges, you can remove the sheath. Plants with sheaths tend to get fungus and scale insects under the sheath. [Scale insects will suck on dormant eyes.] To remove the sheath, blast it with the hose. Once it is wet, it slides off easily.
-Remove all roots outside the pot and all old roots when re-potting.
-Cats bloom only on new growth.
-Cats may be unifoliate (one leaf per stem) or bifoliate (two leaves per stem), depending on species. Bifoliate cats only put out roots once per year – don’t cut the roots. Bifoliates do not like “wet feet.”
ONCIDIUMS take less light than Cattleyas, what I would call extremely bright shade. Grow these in plastic pots in an open media that will retain a bit more moisture. They do not like to go dry for long periods of time between waterings. If the leaves of the new growth are growing out pleated, you are not giving them enough water.
Notes:
-Oncidiums grow midway down the canopy in about 50% shade (i.e., shade that is half way between bright light and dense shade). They have pseudo bulbs—plump dry roots outside the pot.
-They like to stay moist. A media containing sphagnum is a good choice. Loose sphagnum holds 10 times the water compared to sphagnum that is tightly packed so sphagnum can provide a variety of moisture levels.
-Roots die off from age. Roots outside the pot are typically drying – remove from the plant before repotting.
PAPHIOPEDILUM [lady slippers] (multifloral, strapped leaves) will take light at about the same level of the Cattleyas while the (mottled leaved) Maudiae type require a bit less light almost as bright as the Oncidiums. Both types require the same care. Grow them in plastic pots in an open media that retains moisture. They do not want to dry out between waterings.
Notes:
-Roots are brown and hairy (silica that take in water) and want to stay moist all the time. The pale green leaf (strap leaf) requires more light than the mottled leaf type of lady slipper. Otherwise, the care is the same as for the mottled leaf.
-Phragmipedium are similar to paphiopedilum but with sequential blooming. They like a small amount of standing water but still need to be watered from the top.
PHALAENOPSIS are probably the most popular and well known of the orchid genera and are shade growing plants. They grow in shady conditions on the lower limbs of trees in the jungle and like to be slightly damp at all times.
Notes:
-Shade is about 60% (i.e., shade that is more than half way between bright light and dense shade).
-Keep roots moist (not wet) all the time.
-When watering, let the water run through the pot. Make sure the sphagnum growing medium is moist throughout.
-Limp leaves mean too much water or too little water. Check the roots: if rotting, then too much water.
-On the flower spike, once all flowers have dropped, cut above the third eye from the bottom of the spike. This should promote a side shoot that will flower, albeit with fewer, smaller flowers. Only do this once per flower spike per year. Do not try to keep the orchid continuously blooming: the plant needs time to grow and constant blooming requires too much energy from the orchid.
-Phalaenopsis will not grow when it is in flower.
-This is a great “beginner” orchid. Most of the phalaenopsis sold in the US are Asian hybrids. China has at least one mile-long mechanized nursery specializing in Phalaenopsis. Orchid seeds have no exoderm – must germinate in sterile conditions.
-Phalaenopsis require a 15 to 20 degree drop in temperature overnight in the fall to trigger blooms. Overnight temperatures between 50 and 60 degrees for two weeks initiate new bloom here in Central Florida.
All the above-mentioned genera should be fertilized on a regular basis – what is commonly referred to as “weekly, weakly”. A small amount of fertilizer every week during the growing season (i.e., when not flowering). During our rainy season, I highly recommend a monthly treatment of both a topical and systemic fungicide to help prevent fungal infections that are to be expected when plants are too wet for too long.
Notes:
Pests, diseases and mechanical damage:
-Black areas with a yellow line or mushy black areas are actively growing fungal infections: cut ½ inch below the fungus and treat with cinnamon (a desiccant and a natural antifungal) or antibiotic gel (petroleum jelly) to create a water barrier.
-Black areas without a yellow line are fungal infections that the plant has taken care of. Do not treat these areas.
-If really cold weather is forecasted, do not water orchids. They do better in cold weather when they are drier.
-Washing leaves: photosynthesis occurs on the bottom side of the leaf so dust is not the same problem for orchids as for other plants. If you DO need to wash the leaves, use fresh cut lemons or whole milk to dissolve mineral deposits and remove dust.
-Periodically flush orchid pots to remove fertilizer (salt) build up.
-The presenter likes to use insecticides whose Mode of Action is growth regulator (e.g, Knack for Orchids).
-Fertilizer should contain Calcium and Magnesium as well as trace elements.
-BE CONSISTENT – if fertilizing once a week, always fertilize once a week. Orchids suffer otherwise.
-You can chop sphagnum and add it to bark – the compaction of the chopped pieces will determine how much water the sphagnum can hold. Hard bits hold less water than loose bits.
-Pot to root size – orchids like crowded roots.