Baby Plants

I have a grandson who is stationed in Hawaii and he sent me three tiny orchids (Catt, Den, Phal) in 2" pots. What should I do now, repot them? Catherine A.
Things could be worse. Be thankful that he didn't send you lava rock from a nearby volcano. According to Hawaiian folklore, the recipient is cursed for life by Madame Pele, the Goddess of Fire. Each year, tourists take thousands of 'souvenirs' from Mauna Loa only to return them with forgiveness letters following dreadful events in their lives.
'Tiny orchids in 2" pots' pose a challenge for any horticulturalist who, realistically, is facing a 3 to 5 year project. These exotic toddlers are so slow growing that progress is not noticeable for months at a time. The initial goal has to be just keeping the plants alive.
To complicate matters, there are three different kinds of orchids and each has specific growing conditions. The temperatures are the same for all, but the potting media and light levels are not.
It is entirely possible that the plants can stay in their little pots for a few more years. It is easy to tell if they have outgrown their pots - the newest pseudo-bulbs are over the edge and the expected new roots will not be able to direct themselves into the media. If re-potting is necessary, always use the smallest pot (preferably clay) that the roots will fit into. Young orchids dry out quickly so it is important to be vigilant about prompt watering.

What type of greenhouse would you recommend for orchids? We were thinking of building a simple glass structure using sliding doors and sky lights. Marshall N.
You know you're addicted when...your orchid collection has gotten so large that a greenhouse is required. Don't feel bad though. There are many others in the area that are also in the late stages of this 'illness'. Help is on the way.
As long as there are no local zoning regulations regarding the construction of such buildings, then there are two major options: Greenhouse and Sunroom.
Greenhouses are designed for plants only - as many as will fit, usually grown on benches. There are hoses and a potting area and gravel floors, fans, heaters. Sunrooms allow for co-habitation of plants and people. There might be wicker furniture, fluffy pillows, a nice carpet. Plants are plentiful but not in the way.
Both growing areas are best enjoyed attached to the south facing sides of houses so that the owners can walk freely in and out of the structure even in the dead of winter. The warm buoyant air on sunny days will flow into the house adding new life to the residence.
The solar orientation of the structure dictates which kind of orchids can be grown inside. North facing receive little or no direct sunlight so only low light plants will do well there - Paphiopedilums and Phalaenopsis. South facing opens up more orchid options including the intermediate light loving Cattleyas, Dendrobiums, and Oncidiums. Possibilities also exist for the tricky Cymbidiums and Vandas.
Generally, one evaluates their orchid collection's culture needs and weighs those against the feasible orientation of the structure and their pocketbook.

I am unsure about watering cattleyas. I understand that they need to dry out between waterings, but how dry is dry? John B.
It takes years of experience to know exactly when and how to water an orchid - my father has been pondering this issue since 1945. A grower takes into account the season, time of day, outside weather conditions, type and age of the plant, type and age of the potting medium, pot material, genus, hybrid or species, variety, spacing on the bench, and other random factors too numerous to mention.
That being said, Cattleyas, aka 'Queen of the Orchids', are tolerant of less-than-perfect care because they have water storing pseudo-bulbs and can miss a day or two of watering. The rule of thumb is 'thoroughly drench when the medium is no longer slightly damp'.

Friday, December 1, 2006 - 18:00