Why Do My Orchids Die?
In March, Mission Hills Garden Club members learned about the cultivation of orchids from Tom Biggart. He has loved orchids most of his life and has a vast variety of them. He has so many plants that he and his wife had to leave their Kensington home for more land in El Cajon. This was fortunate because it gave him room to buy more orchids. At his El Cajon property, he has a 20 by 40 foot greenhouse. Because he finds plastic pots unattractive, he took up a new activity: pottery. Now he can hide the ugly plastic in pots he creates specifically for his needs. His talk covered general culture of orchids, repotting tips, and what varieties are easy to grow in our area.
Orchids like light, warmth and humidity. They also enjoy moving air. A plant that receives sufficient light will have light green leaves. Without sufficient light, the plant will not bloom. Most orchids grow well in temperatures ranging from 50 to 80 degrees, but there are some that can withstand temperatures as low as 40 degrees Fahrenheit and as high as 90 degrees.
Most orchids need watering once a week; in summer you may need to water them twice a week, and perhaps every ten days or so in winter. Pseudo-bulbs store water and are fat when full. However, when the bulbs shrivel, the plant needs water. With phalenopsis it is important to keep the crown dry; should you get water in it, dry it carefully with a cotton swab. Crown rot is a common cause of death. A soft and mushy pseudo-bulb is definitely suffering from over-watering. Orchids need far less water when they bloom. To water orchids properly, do not stop until the water runs out the bottom holes in the pot. This flushes some of the minerals and salts that our water contains that are not good for the plants.
Orchids prefer 40 to 80 per cent humidity. If they are growing outdoors, you may need to mist them daily on hot summer days. During Santa Ana winds, they may need misting several times a day. Indoor orchids can benefit from sitting on a tray of gravel with water in the tray.
Biggart advises repotting orchids planted in moss immediately as moss encourages dangerous fungus growth and rot. He removes the plant with its roots and moss from the pot. If the plant has no live roots, he removes all the moss first. Next, he puts the plant and fresh, damp moss in a plastic bag, sprays it with some fungicide, blows the bag up, and seals it completely. The bag stays in a dark place for a few weeks. Once he sees new roots, he carefully removes the moss. Finally, he plants the now fungus-free orchid in a mixture of equal amounts of orchid bark and Perlite. Some people prefer using equal parts fir bark, charcoal, and perlite.
A happy orchid plant can have roots growing over the edge of its pot. When it has grown many bulbs and is over-flowing its pot, or if the plant is not thriving, it is probably time to divide the plant or re-pot it in a bigger container. Ideally, the plant has finished blooming before being re-potted. (Biggart never waits to re-pot orchids planted in moss.)
If you choose to divide your orchid, each section should include three to five bulbs. The easiest and safest way to divide a cymbidium is to throw it down onto a hard surface. This splits the plant naturally and avoids the need to separate bulbs by hand. Prepare the pots with new mix. While disinfecting the pots before using them is a wise precaution, Biggart does not do so. He does give his orchids a fungicide treatment if it is necessary, even if he has not treated the pots.
Whether he divides a plant or gives it a larger container, he will leave just enough room for a year or two of new growth. He puts new orchid mix in the pot and sets the plant in the center, towards the rear of the pot. “Eyes” face forward. If the plant is rocky, he stabilizes it with a stake. This is when labeling the plant is important. Until it produces new roots, it needs a warm, humid, and shaded area and its leaves misted every day.
In addition to growing in pots, mounting orchids so the blossoms hang in a cascade of flowers is closer to the way they grow nature. This is a common practice in Taiwan.
Another tip Biggart gave us was how to encourage phaleonopsis to bloom more than once. Spent spikes often produce another batch of blossoms so long as the spikes are green. Spikes should not be cut until they have completely turned brown.
Biggart concluded his talk by discussing some of the best outdoor orchids for San Diego. He mentioned several from reed-stem epidendrums, which grow, both in the ground and in pots and flower constantly with a variety of bloom colors, to laelia purpurata and its hybrids. Many of the Australian orchids grow well in our climate. Another easy-to-grow orchid is the cymbidium which grows rapidly but is not terribly easy to divide. These plants need the drop onto concrete treatment to facilitate the process.
Remember the Mission Hills Garden Walk on Saturday, May 12. Tickets are available at Mission Hills Nursery. This is our 14th walk! The May 23rd meeting will be with Duane Wheeler speaking on How Organics Changed My Garden. Meetings are held from 6 to 8 p.m. at 4070 Jackdaw, Mission Hills Church of Christ.
Category: Life Style
