February To Do List

 General

• In general, most orchids should still be kept fairly dry in winter even during warm periods.  If you grow on the coast near the ocean, humidity is usually higher so occasional misting (with pure water, if available) or light watering in extended periods of warm or Santa Ana conditions may be warranted. If you grow further from the ocean, where orchids experience even warmer temps and low humidity and are openly exposed to Santa Ana winds, then you may need to mist and water more often to avoid dehydration, but avoid watering excessively.  Too much water will encourage plants to send out new growths, which will not fare well when the weather turns cold again.  
• When you do water, do so in the morning and avoid wetting buds and flowers to minimize botrytis (fungal) spotting.  Also keep tabs on the ten day weather forecasts and avoid watering if cooler and/or wet weather is predicted. One wants to make sure orchids are kept on the dry side to allow them to tolerate the cold winter nights we tend to experience in Southern California.  If February brings more normal, cooler weather than January, cut back on water and avoid fertilizing as cooler days and nights prevail.
• Maintain cold-sensitive, warm growing orchids (phals, paphs, tolumnias, most vandas and warm growing dendrobiums and cattleyas such as violacea, dowiana and their hybrids) inside or in a greenhouse to protect them from night temperatures below 50o; however, watch under leaves for spider mites and other pests that flourish under dry, less humid conditions.  An excellent article on ‘Cold Tolerance of Orchids’ by Sue Bottom of the St. Augustine Orchid Society can be found on their website.
• Separate cold loving orchids, including odontoglossums, miltonias, pleurothallids, masdevallias, draculas, from orchids that need a drier winter rest  (many encyclias, deciduous dendrobiums, catasetinae and some terrestrials) so they can be freely watered and fertilized to allow growth but also avoid overwatering and protect them from freezing temps. Take this opportunity to divide or repot these cool growers during their winter growth period to encourage new growth and avoid the stress of repotting during the warm season.
• Winter blooming cattleyas and cymbidiums should be in bud or full bloom. Provide adequate water and weak fertilizer, but do so in the mornings so plants dry out before nightfall. Avoid wetting buds and blooms to minimize fungal spotting.  Stake cymbidium spikes to guide inflorescences for support of buds and blooms.
• Maintain good hygiene practices to minimize transmission of pests and viruses. Practice careful watering and remove problem plants and debris from the healthy collection. Old dying leaves even on healthy plants will succumb to diseases and decay so keep your growing area picked up.
• Watch for fungus, bacterial rot and cold burn in cold and wet weather. Remove infected tissues and treat accordingly. Diligently check psuedobulbs and canes for discoloration and firmness. Though some change is normal, it can also be indicative of black rot. If any pseudobulbs or canes are soft, mushy, and possibly exuding dark fluid, isolate and treat. An excellent article to read " Is There a Fungus Among Us?" (A.O.S. Orchids Magazine, Aug. 2012) or refer to the AOS website.
• Many paphs will be coming into bloom at this time. These terrestrial orchids should kept on the warmer side and not be allowed to completely dry out due to their sensitive hairy roots. Although they grow all year long, paphs grow more slowly in winter but can be repotted at this time if warranted, since they are one of the few orchids that can be repotted at almost any time and benefit from it every 1-2 years. Repotting should be done more carefully at this time to avoid plant damage, particularly to roots that are needed for quick recovery.  After repotting, observe plants carefully to detect and intercept disease damage.
• Spring show season is beginning so be sure to stake and groom your plants to have them look their best for judging.  When staking, be sure to not restrict the new soft growth tips.  Permit growths to expand naturally and tie securely at the bottom and then further up when stems start to harden.  Spikes and flower can be encouraged to open sooner by increasing the ambient temperatures and allowing enough time for the flowers to mature fully. 
• More details on specific genera for January and February are available on the AOS website.

Indoors and Greenhouse

• Carefully monitor greenhouse temperatures and check that circulating fans, automatic vents, humidifiers and heaters are in good working order.
• Use a humidifier or mister to keep humidity up due to heavier use of fans and heaters in winter.  In absence of a humidifier, wet down floor to increase humidity: however, avoid puddles of standing water and maintain good hygiene by keeping floors clean.
• Continue to provide good air circulation for indoor plants to discourage diseases and pests such as mealy bugs and scale. Be sure to check all edges of the pot and neighboring pots. Pests, especially mealy bugs also can be found on the bottom of pots. Treat early to avoid spreading to other plants.
• Cut back on watering and frequency of fertilizing in winter. Err on the side of under fertilizing as active growth is at a minimum and excess fertilizer is unnecessary. This will minimize root damage and growth of soft tissues. 

Outdoors

• Continue to monitor and control snails, slugs and other pests as cooler wet weather will bring them out. They can do considerable damage to plants in short order.
• Try not to use water that is much cooler than the plants as their tissues can be shocked. Watering early in the day will facilitate that and allow plants to dry before nightfall in order to minimize bacterial and fungal diseases.
• Most cymbidiums are now in spike or bloom and may be starting to produce new growths.  They should be kept on the dry side, but do not allow them to completely dry out.  If you are using a lower nitrogen fertilizer, consider increasing the nitrogen content (20-20-20 or 30-10-10) and the frequency of fertilizing as you see new growths emerging. Stake spikes early to train them to grow upright while the spikes are flexible. 
• Overgrown cymbidiums should be repotted and divided after old blooms drop off or for plants where the old media has begun to break down.  A excellent source of info on repotting, including pictures, can be found on the Casa de las Orquideas website.
• Members of the Catasetinae family (catasetums, clowesia, cycnoches, and mormodes) are now in their dormant period as evidenced by the yellowing and loss of leaves. Note that some actually initiate spikes at the outset or during their dormant period.  Eliminate water and fertilizer altogether until spring when new roots are 3-5” long, then water and fertilize heavily as recommended by Fred Clarke on his website.
• Most phalaenopsis are very sensitive to cold and should be inside your home or in a greenhouse and in spike or in bloom.  Stake spikes early to train them to grow upright for optimal display of blooms.