Care & Feeding Your Orchids
Our intention here is to give you some very basic guidelines on how we manage to water & feed our orchids. As many of you already know, there are many variables that can influence this perfect state of balance. I hope you find this information useful, but please understand that our growing conditions probably vary from yours, so please keep that in mind. Careful observation of your plants, your daily weather and what type of orchids you are growing, coupled with appropriate care will have your orchids not just thriving, but flowering.
Some thoughts on Watering
Watering orchids is a fine balance between how loose or dense your media is, the type of orchid and what the weather is doing...hot & dry or cold & damp. All 3 factors must be considered every time you water. We like to grow in a very loose mix ( 1/2 New Zealand radiata Pine Bark & 1/2 perlite) which does dry out quickly but allows us to water 3 times a week with our typically warm, sunny Hawaiian weather. Should our weather become very wet, cool or not as much sun we will eliminate 1 watering cycle so that the plants will dry out.
Should you start seeing wrinkling on the pseudobulbs of oncidiums,zygopetalums & miltonias, on the canes on dendrobiums or very soft (limp celery) leaves on vandas, paphiodilums, masdavallias or phalenopsis your plants are too dry.
If your orchids are not getting enough water they will tap into the water reservoir of the older bulbs & canes in order to generate new growth or produce a flower spike. Monopodial orchids without bulbs or canes are most vulnerable as if they get dehydrated it will compromise the integrity of the entire plant.
Vandas in particular need to be watered sufficiently, which means almost daily. We grow ours with no media & water daily. The best is the double water method of watering generously and then 10 minutes later watering again with either fresh water or fertilizer. This primes the plant for better water uptake on the second watering.
Always water in the morning so that the plants do not becomes stressed during the heat of the day or 'go to bed with wet feet'. Wet roots at night can cause root rot, so by watering early in the day the plants have the opportunity to dry out before the evening rolls around.
Time Release Fertilizer
We apply time release fertilizer once the plant has established a good root system in their new pot. If we continue to grow the plant at our nursery beyond 1 year in that pot we top dress with another round of the 13-13-13.
Nutricote 13-13-13 270 day release (9 months)
Nutricote 18-6-8 90 day release (3 month)
Water Soluble Fertilizer
As we are commercial growers primarily of blooming orchids, not just near blooming size, we have a very thorough and consistent fertilization program as our goal is to turn benches of flowering orchids in a timely fashion. So, in addition to our top dress, time -release nutricote, we also fertilize with water soluble fertilizer that is injected through our irrigation system.
We typically rotate between - 20-9-20 and 13-2-13 both produced by Technigro.We foliar feed every 2 out of 3 waterings or basically 2x a week, the 3rd watering being just fresh water to flush the pots of any salt build up. Fertilizer is mixed at 150 ppm.
Fish Emulsion is also injected once every 2 weeks at 50 ppm (parts per million).
General Guidelines for Dendrobium, Cattleya, Oncidium, Intergeneric Oncidinae, Miltonia, Pahiopedalum, Zygopetalum and Masdavallia
- Temperature: 55 – 85 degrees
- Light: filtered (30 -50 % shaded) no direct sun
- Watering: 3 times week (once with fertilizer) in the morning for 3-5 minutes. Allow the plant to moderately dry out in between watering.
Do not water any orchids at night, as that will increase the chance of root decay from staying too wet.
- Fertilizer: Water heavily with a well balanced, liquid, foliar fertilizer such as 20-20-20 once a week. Water plant first, and then water again with fertilizer.
- Humidity: A pebble humidity tray helps keep the air moist around your plant if you are in an extremely dry area. Bathrooms are also good, for they tend to be more humid.
Miltonia, Paphiopdilem, Intergeneric Oncidinae and Zygopetalum and Masdavallias do not like to dry out completely in between watering and I suggest a humidity tray for these and more frequent watering in warmer weather.
Cattleyas and Dendrobiums like to dry out completely in between watering.
The American Orchid Society has individual culture sheets for many different orchid genus that can be down loaded from their web site linked below.
Membership to the American Orchid Society not only provides you with a beautiful magazine, -Orchids, 12 times a year which is packed full of information, but a member discount on books and gift items purchased through the Society.
Orchid Pest Management
Here in Hawaii we have some of the best year round weather and growing temperatures, but that can also mean year round issues with pests, fungus & bacteria. All of our plants are greenhouse grown under plastic (except paphiopedilum...they are under just shade cloth and are subject to all our rain), with just shade cloth for walls which does not provide a barrier for insects or fungal/bacteria spores.We have to be diligent with a regular spray program to prevent pest problems and plant loss due to fungal and bacterial issues. It is always best to keep these issues at bay, rather than treating the problem once it has become established.
The following information is meant to be a BASIC Guideline of how we prevent and/or treat Pests and Diseases. Please always read labels, mix at the correct label rate and follow the correct application schedule. Most importantly, always wear protective gear (Gloves, eye proctection, protective clothing) when mixing or applying any chemical and adhere to the proper re-entry levels.
Pesticides for Insect Control
Avid - Mites, Foliar Nematodes
Orthene - Aphids, scale
Admire - Thrips
Dipel - caterpillars
Conserve - Spider Mites
SlugFest - Slugs, Bush Snail
Distance - Scale
Dursban - Most sucking type insects
Rhapsody - We use this especially on our keiki production, small plants just out of flask.
Pentahalon - All purpose, both fungus and bacteria
Heritage - All purpose
Aliette - All purpose
Subdue - good for preventing root rot, pythium & phytophtera