Cultural Notes
Masdevallia
In general
Masdevallia orchids are cool growers. They love a cool, moist environment with plenty of air movement to remind them of their origins in the high country of South America. They do not have pseudo bulbs like many epiphytic orchids, only fleshy leaves to hold water and nutrient. One should be careful therefore to maintain moisture at the roots and in the environment. It is still important not to over water, never keep the medium soaking wet. For the reasons above it is vitally important to keep the growing medium sweet. If it decays it will rot the fine root systems and the plant will collapse. For this reason we recommend repotting annually.
Potting
Potting mediums should be either good quality aged pine bark sieved and graded, Sphagnum Moss or more recently coco coir fibre mixed with Perlite. Our favourite method is to use 1/3 to 1/2 pot of bark then add the orchid Osmocote then top off with Sphagnum Moss. We find this allows good drainage while still maintaining the benefits of Sphagnum Moss that Masdevallias really like. The Osmocote maintains excellent nutrition for the plant between annual repotting.
In the past year good quality coco coir fibre has become available. We are currently potting many plants in this medium, mixing it with 20% coarse Perlite and feeding with Orchid Osmocote, which as usual we place in the bottom 1/3 of the pot. Results look promising with easy watering while the fibrous nature of the material assures plenty of air to reach the roots. Ready mixed coir & Perlite available at the nursery.
Conditions:
Masdevallias need to be well shaded in Summer to keep the plants cool and the environment humid. If possible try to keep the temp. under 30C, a few hours warmer won't matter as long as you have humidity. Constant dry heat will cause the plant to drop its leaves and collapse. In Winter try to give bright airy conditions, humidity is usually high any way. Some overhead cover is essential in Winter or they may become too wet. Minimum temperature should be 5C for most, though be aware there are some warmer growers. Masdevallias will sometimes tolerate a light frost but try to avoid this if at all possible.
Summary
Cool moist airy conditions free from frost. Avoid hot and dry. Pot annually, do not divide too small. Feed Osmocote or Manutec Orchid Food. Keep free from pests especially Aphids. Do not over water.
Masdevallias may be grown indoors if you have light but not direct sun on a window sill or similar. As humidity is low indoors leaves will need misting daily and plants grown on wet gravel or plunged in Sphagnum Moss. You may be surprised just how well they grow indoors. If you live in a climate with long hot summers they may well prefer it indoors at least for the Summer.
Zygopetalum Alliance Hybrids & Cymbidiums
Feeding
Orchids, contrary to popular believe, do require fertilizer to grow well and produce plentiful flowers. You can feed with either slow release or liquid food. Best of all is a combination of both. We recommend and sell Osmocote High K 8-9 months slow release and Manutec orchid food. We place the Osmocote pellets in the bottom 1/3 of the pot while potting, this assures good long term feeding especially good for flower production. At the same time 1/4 strength Manutec is fed every 7-10 days in all but the colder months. Osmocote can be safely used with Sphagnum moss when placed near the bottom of the pot, NEVER on top.
Watering
Orchids in pots need attentive watering. Too much will rot the roots and too little inhibits growth and flowering. Make sure your orchids have almost dried out before the next watering. During peak growth time late Spring and Summer plants will tolerate and enjoy more water but beware the cold weather and keep much drier. Make sure to keep the leaves of Zygopetalums especially dry in winter to avoid fungal problems.If in doubt about the health of the root system lift the plant from the pot and have a look. If the roots are pulpy and black repot into fresh mix after trimming all dead roots away. Indication of poor roots is often seen by the leaf tips turning black or leaf drop from older bulbs, old bulbs may even be decaying and soft.
Yellow leaves
If the leaves are healthy but yellow this indicates light levels are too high or a lack of fertilizer or both. Plants will adapt to high light but 50%-60% is usually about right. Odontoglossums and Masdevallias need about 80% shade. Morning sun is good but try and get a position that gets sun for most of the day.
Diseases
Fungal bacterial & viral diseases can effect orchids.EcoCarb in conjunction with Eco-Oil will keep plants fungal free. Good air movement is essential to maintain healthy plants. .Grow on benches or raised off the ground. Space, so the leaves only just touch.
Pests
Few things effect orchids but they need control or growth will deteriorate. The two main pests are Scale and Red Spider Mite. Less of a problem with Cymbidiums but serious with natives, Masdevallias and Odontoglossums are Aphids. Mealy Bug may effect plants in warmer glass house conditions. The simple effective and non toxic remedy is Eco-Oil (see Sundries) we use this exclusively for all our orchids and find it a joy to use and have no insect problems. Made from eucalyptus and other natural plant material this spray can be used without use of protective clothing and will not harm wildlife or the gardener.It can be used throughout the garden and is ideal for orchids in particular.
Potting medium
Orchids are grown in a bark based medium or Sphagnum Moss, generally the bigger the pot , the larger the bark size. Buy special orchid bark such as Bio-Gro. Sphagnum Moss must be fresh. Do not over compress moss when potting. Firm with fingers until plant is securely held in the pot. Water with care. Moss holds many times its own weight in water.
Temperature
Many orchids will grow cold and tolerate light frost but if they are grown a bit warmer they will make stronger growths, more leads and better roots. To produce flower spikes Cymbidiums must have mature growths by early summer. If this does not happen plants take two years to mature growths and hence flower every other year.
Summary
The secret to growing and flowering orchids is to produce healthy roots, healthy foliage and strong new growths as early in the season as possible. Cymbidiums and other genera don't grow much when the temperature is below 10C or above 35C. For this reason you should select growing areas to provide conditions for the majority of the time. Watch out for the signs that something is wrong; dropping leaves, black leaf tips etc. Inspect the root system first. If that's O-K check out the other cultural factors discussed above. Remember NOT to over feed, NOT to over water and keep the plants spaced out.
Odontoglossums
In general
The Odontoglossum Alliance is large and diverse with some of the most colourful, unusual and showy flowers in the orchid family. They have their origins in the Central and South American high country, sometimes very high. This means they are in the main cool growing often very cool. What this means to you is that you must provide conditions appropriate for high altitude plants. This can be a problem if you live in a warm climate, but a little ingenuity with fans, misters or air conditioning and shading will usually solve the problem. In the past years modern hybridizing has produced a whole range of Odontoglossum Alliance hybrids usually involving Oncidiums that are exceptionally heat tolerant. In many cases these plants will grow alongside your more traditional Cymbidium, Zygopetalum or native orchid. For the cooler type i.e. Odontoglossum and Odontioda of the O. crispum line, we suggest a maximum temp. of 30C, lower if possible. Minimum should be 5C with lower than that, even a light frost, not fatal.
For the warmth tolerant varieties i.e. Odontocidium, Wilsonara, Colmanara, Burrageara and most others that end in '- ara' we can raise the maximum temp. to 35C+ but under 40C. Lower is still better. Winter min. temp. can still be down to 5C but lower is no good, warmer is better.
General growing conditions therefore are cool, airy and humid. Shade to keep cool but don't put them under the benches in the dark. Give them plenty of light in the winter, early spring and late autumn. Be sure not to keep them in the shade you use in the summer or you will get no flowers and weak growth.
Watering
This should be carefully attended to. Odonts. do not like over watering nor do they like to be dry for very long. For this reason the correct potting medium in good condition is essential. Annual repotting is usually recommended. Decaying and sour medium is difficult to water correctly and the roots will soon stop growing and turn rotten.
Potting
Should be done with good quality medium size composted pine bark mixed with 20% coarse Perlite. If you can get it, very coarse fibrous peat moss with little or no fines should be added also at about 20%. The other traditional potting medium is fresh Sphagnum Moss. As with the Masdevallias I often use pine bark in the bottom half, then add Osmocote then top off with moss, it works well but usually still only lasts a year. We have recently potted a large number of Odonts. in coir and Perlite. We are very pleased with the results so far.
Pests and Diseases
We currently use the full range of products from Organic Crop Protectants for total control of all the nasties which may attack your plants.(See Sundries) The only other pest you may and will get are slugs, snails and garlic snails. Use Defender pet safe snail bait regularly.
Things to watch in Odontoglossum culture
Odonts. like good water, not too alkaline and no salt. If you can use rain water so much the better. Fertilizer in liquid form must not be too strong. When we use Osmocote High K we only use Acadian Seaweed extract and Aminogro as stimulants every 4 weeks. Leaf tip die back commonly becomes a problem thru over feeding and poor water. It will be worse if the plant's root system is not in good condition.
In summary
Odontoglossums like an airy humid and cool environment. Stuffy hot houses definitely don't suit. Pot annually in Spring or Autumn depending on growth. Odonts. are potted when the new growth is an inch high, not when dormant. Odonts flower on young plants but don't leave flowers on for too long. Many growers believe flowering every two years gives the plants a better chance to flower well. Leaf colour should be green and shiny. Pale yellow leaves suggest too much light or lack of Nitrogen. Give plenty of air, when its hot and dry, make sure you maintain humidity which should be 70% - 80%. Bulb shrivel will occur if you leave flowers on for too long or the root system is inactive or dead.
If all this sounds too hard well its not really, and its what most of your orchids will need to thrive. Odonts. perhaps are more fussy but grow them well and you will be well rewarded and all your companion orchids will benefit from the better climate you have created.
Miscellaneous Genera
As above.