Humidity

Question:
I've heard that orchids like humidity. We have had our air conditioner running this summer which takes much of the moisture out of the air. What can I do to create more humidity? Nancy M
Answer:
It is true that orchids like humidity, however, the environment does not have to be a dripping rainforest. Humidity is defined as the amount of water vapor in the air and orchid growers generally strive for at least 50% which is comfortable for you as well as the orchids.
During the summer, the best location for your non-blooming orchids is outside (avoid full sun) where the warm temperatures, fresh air, and high humidity mimic native jungle conditions (Blooming orchids are always best kept inside due to the fragileness of the flowers).
Orchids that are grown inside year round may require supplemental humidity from either a humidifier or a humidity tray. The first step is to measure the humidity in the vicinity of the orchids using an inexpensive hygrometer. If the readings are low, the orchids would appreciate the addition of an external source of water vapor. A humidifier will add moisture in the entire room whereas a humidity tray will add moisture just around the plants.
There are two types of humidity trays - (1) the old-fashioned style where gravel is placed into a tray and water is added to maintain a water level that is just below the top of the rocks. The plants are then placed on top so that as the water evaporates from the tray, the humidity level around the plants is increased. (2) the newer style where the plants sit on top of a plastic grill that sits on top of a tray filled with water. Growers rave about the new type ($10-$17) which are easier to clean and offer a flatter surface to sit orchids on.
Always try to avoid the temptation of misting the flowers as a method for increasing humidity. The water droplets are too large to stay airborne and may cause fungal problems on the delicate petals.
Question:
The tag in my orchid pot simply says ‘Z mackayi’ (the flowers are green with purple veins) – what does this mean and how do I care for it? Elizabeth H
Answer:
You are fortunate to have a plant tag in your pot as many orchids sold today are nameless. A good plant tag informs the owner of the general orchid type (or genus), the hybrid name, and hopefully, the commercial growers name should you have any questions.
The nomenclature of orchids can be very confusing as the genus is often abbreviated for simplicity. For example, the genus Dendrobium is commonly shortened to Den or D and Phalaenopsis becomes Phal or P. Your plant belongs to an unusual orchid genus called Zygopetalum, sometimes written Zygo, or Z. The next word on the tag is the hybrid or species name which further describes the plant but is usually only important to collectors or strict orchid enthusiasts. In your case, mackayi is the Zygopetalum species, a.relatively rare and fragrant orchid closely related to those found attached to trees in the wild.
The culture for Zygopetalums is similar to Oncidiums - Filtered light, water once or twice a week thoroughly and provide temperatures between 60 and 90 deg F. Zygopetalums tend to grow in clumps so repotting won't have to be addressed for several years.

Question:
I have had my orchid for about 4-6 weeks. All the flowers have bloomed and are starting to fall off. Am I doing something wrong? Leigh-Ann C
Answer:
The bloom duration of an orchid depends on a number of factors including the type of orchid, how long the plant was in bloom when you received it, and how the plant was cared for once in your possession. It is reasonable for your orchid to last 4-6 weeks. Many popular orchids last this duration though Phalaenopis bloom for an incredible 3 months and Cattleyas only 2-3 weeks.
Unless you received your orchid completely in bud (no flowers open), the orchid had been blooming for some time – perhaps a few days but maybe a few weeks or more. One clue in determining the age of the flowers is to notice whether the plant has any buds remaining or whether the flowers are in full bloom.
Finally, it is a good idea to thoroughly water the plant twice a week while it is in bloom so that the orchid is not stressed in any way. At first signs of stress, the plant will abandon the flowers and concentrate on survival.

Date: 
Monday, September 1, 2003 - 19:00