Monthly To Do Lists

January

General

Short days and cold nights in January will keep most of your orchids in a semi-dormant growth state but Fall/Winter blooming orchids will initiate spikes at this time. Watch them very carefully and cut back on water and fertilizer as cooler days and nights prevail.
Protect your outdoor orchids from winter rains. Keeping them on the dryer side will allow them to tolerate the cold winter nights we tend to experience in Southern California. Water and fertilize sparingly during winter warm spells.
As watering and fertilizing practices diminish for winter, be sure to leach your plants thoroughly. Make your last thorough watering a leaching process in order to address 'salt built up' issues before diminished watering starts. Roots should readily be able to absorb the little water and nutrients that they may get during this period. Roots heavily encrusted with excess minerals are not able to absorb the ones they need and may develop deficiencies or even excess toxic levels during dryer conditions.
Keep 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 50°F. An excellent article on ‘Cold Tolerance of Orchids’ by Sue Bottom of the St. Augustine Orchid Society can be found in their October Newsletter (pgs. 9-11)
Cold loving orchids, including odontoglossums, miltonias, pleurothallids, masdevallias, draculas, will thrive in cool weather and respond by initiating growth so continue to water and fertilize them during this period but also protect from freezing temps. Take this opportunity to divide or repot them 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 by now. Provide adequate water and fertilizer, but do so in the mornings so plants dry out before nightfall. Stake cymbidium spikes to guide inflorescences for support of buds and blooms.
Maintain good hygiene practices to minimize transmission of pests and viruses. Watch for fungus, bacterial rot and cold burn in cold and wet weather. Remove infected tissues and treat accordingly. More information on treating these disorders can be found on the AOS website.
More details on monthly checklist items for specific genera can be found on the AOS website

February

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.

March

General

Continue to follow recommendations for February as low night temperatures throughout February and early March will likely delay onset of the initiation of spring growth.
Prepare for a busy spring cleaning period. Purchase orchid supplies in anticipation of the spring potting season.
Avoid reusing pots as they carry potential for viral and bacterial infections. If you must reuse pots, disinfect plastic pots by soaking in a bleach/soap solution overnight. Clay pots can be reused by cleaning, followed by sterilizing in an oven at 425°F for 2-3 hrs.
As temperatures and light intensity increases during the month, consider re-positioning shade cloth or moving orchids to avoid damaging effects due to increased light and heat as appropriate.
To facilitate new growth consider positioning the emerging growths in the direction of the sun.
More details on specific genera can be found on the AOS website

Indoors and Greenhouse

April

General

Review and continue to follow recommendations for March since continued cool temperatures throughout March, particularly on the coast, has delayed Spring flowering and onset of growth for some species and hybrids.
Fine tune the shading of orchids as heat and light continue to increase.
Remove with sterile utensils any dead flowers or leaves that were damaged by bacterial rot or fungal rot, being careful not to contaminate clean plants.
If not done yet, spray benches and growing areas with Physan to decrease possibility of bacterial and fungal diseases.
April brings on new growth for many orchids and the opportunity to repot and divide those orchids that initiate new root growth at this time. Try to repot when roots are small and just beginning to emerge in order to minimize damage to soft tissues and avoid transplant shock, giving plants a head start for the upcoming growing season.
Repot when orchids have begun to over grow their pots and/or when media has started to break down. Also consider repotting plants that have been in pots for 2 or more years and are existing, but not thriving. Repotting can revitalize and provide new vigor to such plants.
It is helpful to thoroughly rinse and soak all media prior to potting. Dry media tends to wick moisture away from plants. Then keep plants relatively dry to encourage root growth. If you prefer to repot using dry bark mixes, water newly potted plants thoroughly (2-3x), then keep on dry side to stimulate root growth.

May

General

Increases in day length and drastic changes in light levels this month may require repositioning of plants to avoid overexposure to sun. Although cattleyas, dendrobiums and cymbidiums thrive in high light levels, phalaenopisis, miltonopsis, masdevallias and other lower light plants can easily burn. For most orchids, one wants to have light grassy green leaves. Dark green leaves suggest too little light, while yellow colored or red tinted leaves usually indicate too much light.
Increasing winds result in additional dust build up on your orchid leaves. This provides the perfect environment for harboring mites. Treat accordingly.
As your flower spikes grow taller avoid changing the orchids orientation to the light to avoid flowers being twisted on the stems. For paphs, do not stake to early or the stems will not be as strong and flower will be in "nodding" position.
May should be the height of growth and repotting season as new roots emerge from pseudobulbs or fans. Try to repot when roots are small and just beginning to emerge in order to minimize damage to soft tissues and avoid transplant shock, giving plants a head start in the growing season.
Repot when orchids have begun to over grow their pots and/or when media has started to break down. Also consider repotting plants that have been in pots for 2 or more years and are existing, but not thriving. Repotting can revitalize and provide new vigor to such plants.
The repotting process can be overwhelming so set aside plants and repot a few every day to ease the process.
As you repot and divide your plants, set aside any extra divisions as donations for the POS auction or for silent auction at the meetings. It will prevent overcrowding of your benches and make someone else happy to get a piece of your prized plant.

June

General

Continued increases in day length and drastic changes in light levels this month may require repositioning of plants to avoid overexposure to sun. Although cattleyas, dendrobiums and cymbidiums thrive in high light levels, phalaenopisis, miltonopsis, masdevallias and other lower light plants can easily burn. For most orchids, optimal light levels are indicated by light grassy green leaves. Dark green leaves suggest too little light, while yellow colored or red tinted leaves usually indicate too much light.
Increasing winds may result in additional dust build up on your orchid leaves. This provides the perfect environment for harboring mites. Treat accordingly. During warm weather, pests and diseases can proliferate very quickly and spread throughout the collection. Carefully inspect plants for scale and aphids and treat early to minimize spread. As always, follow good hygiene practices to minimize transmission of pests and viruses.
June continues the growth and repotting season for many orchids (cattleyas, oncidiums, dendrobiums) as new roots emerge from pseudobulbs or fans. Try to repot when roots are small and just beginning to emerge in order to minimize damage to soft tissues and avoid transplant shock, giving plants a head start in the growing season. Also repot when orchids have begun to over grow their pots and/or when media has started to break down. Consider repotting plants that have been in pots for 2 or more years and are existing, but not thriving. Repotting can revitalize and provide new vigor to such plants.
As you repot and divide many of your plants, set aside the extra divisions as donations for the POS auction or for silent auction at the meetings. It will prevent overcrowding of your benches and make someone else happy to get a piece of your prized plant.

July

General

Avoid excessively high summer light levels and temperatures this month by providing sufficient shade, increased air movement, and watering/misting to cool plants and prevent them from drying out. This is particularly important for individuals who live and grow in inland areas.
Although cattleyas, dendrobiums and cymbidiums thrive in high light levels, phalaenopisis, paphiopedilums, miltonopsis, masdevalias and other lower light plants can easily burn. They also are readily stressed by high temperatures so try to move them in cooler areas of your growing structures. For most orchids, one wants to have light grassy green leaves. Dark green leaves suggest too little light, while yellow colored or red tinted leaves usually indicate too much light.
July continues the growth and repotting for some orchids (cattleyas, oncidiums, dendrobiums) as new roots continue to emerge from pseudobulbs or fans. Try to repot when roots are small and just beginning to show in order to minimize damage to soft tissues and avoid transplant shock, giving plants a head start in the growing season.
Repot when orchids have begun to over grow their pots and/or when media has started to break down. Also consider repotting plants that have been in pots for 2 or more years and are existing, but not thriving. Repotting can revitalize and provide new vigor to such plants.
As you repot and divide many of your plants, set aside the extra divisions as donations for the POS auction or for silent auction at the meetings. It will prevent overcrowding of your benches and make someone else happy to get a piece of your prized plant.
Continue to follow good hygiene practices to minimize transmission of pests and viruses, particularly during the warm summer months when pests and diseases can proliferate very quickly and spread throughout the collection. Carefully inspect plants for scale and aphids and treat early to minimize spread.
More details on specific genera can be found on the AOS website

August

General

To avoid excessively high summer light levels and temperatures for your plants provide sufficient shade, increase air movement, and increase frequency of watering/misting to cool plants and prevent them from drying out. This is particularly important for individuals who live and grow in inland areas, although temperatures on the coast also should be high during this period.
Although cattleyas, dendrobiums, encyclias and vandas thrive in high light levels, phalaenopisis, paphiopedilums, miltonopsis, masdevalias and other lower light plants can easily burn. These genera also are easily stressed by high temperatures so try to move them to cooler areas of your growing structures or bring them inside. Make sure they receive adequate water, paying particular attention to mounted plants.
With the exception of some warmer growing cattleyas and dendrobiums, most of your orchids should be repotted by now. Watch for the emergence of new roots from pseudobulbs before repotting the warm growers. Repot when roots are small and just beginning to show in order to minimize damage to soft tissues and avoid transplant shock, giving plants a head start into the growing season.
Continue to set aside extra divisions or duplicate plants as donations for the POS auction or for silent auction at the meetings. It will prevent overcrowding of your benches and make someone else happy to get a piece of your prized plant.
Maintain good hygiene practices to minimize transmission of pests and viruses, particularly during the warm summer months when pests and diseases can proliferate very quickly and spread throughout the collection. Carefully inspect plants for scale and aphids and treat early to minimize spread.
More details on specific genera can be found on the AOS website

September

General

In spite of the day length becoming shorter in September, this month can still produce very warm days for continued growth of your plants. Watch them carefully and provide adequate water and fertilizer before tapering off when warm days begin to wane.
Some cattlyeas and other genera (dendrobiums, oncidiums) are still in active growth mode so take the opportunity to repot those you may have missed before month’s end to allow enough growth before the onset of cooler weather and initiation of the dormancy period.
Maintain good hygiene practices to minimize transmission of pests and viruses, particularly during the warm summer months when pests and diseases can proliferate very quickly and spread throughout the collection. Carefully inspect plants for scale and aphids and treat early to minimize spread.
More details on specific genera can be found on the AOS website

October

General

Shorter days and cooler nights in October will be the signal for orchids to slow down and prepare for winter’s rest. Watch them carefully and cut back on water and fertilizer as cooler days and nights prevail. Protect outdoor orchids from the first fall and winter rains.
Fall blooming cattlyeas and cymbidiums are beginning their blooming season. Provide adequate water and fertilizer but do so in the mornings so plants dry out before nightfall.
Maintain good hygiene practices to minimize transmission of pests and viruses. Watch for fungus and bacterial rot as weather cools and wetter conditions prevail.
More details on specific genera can be found on the AOS website

November

General

Shorter days and cooler nights in November will slow down the metabolism of your orchids and initiate spikes on Fall/Winter blooming orchids. Watch them carefully and cut back on water and fertilizer as cooler days and nights prevail. Protect outdoor orchids from winter rains.
Bring in cold-sensitive, warm growing orchids to protect them from night temperatures below 50°.
Fall/winter blooming cattleyas and cymbidiums are either in bloom or preparing for blooming. Provide adequate water and fertilizer but do so in the mornings so plants dry out before nightfall. Stake cymbidium spikes to guide inflorescences for support of buds and blooms.
Maintain good hygiene practices to minimize transmission of pests and viruses. Watch for fungus and bacterial rot as weather cools and wetter conditions prevail.
More details on specific genera can be found on the AOS website

December

General

Short days and cold nights in December will slow down the metabolism of most of your orchids and initiate spikes on Fall/Winter blooming orchids. Watch them very carefully and cut back on water and fertilizer as cooler days and nights prevail.
As watering needs of most plants decrease during the winter, be sure to leach your plants thoroughly. Extend your last watering to remove any accumulated salt built-up in the substrate and root system. Excess mineral built-up prevent plants from absorbing the fertilizer and nutrients they need and may lead to deficiencies during dryer conditions. The St. Augustine Orchid Society hosts a very good collection of articles on water quality.
Protect outdoor orchids from winter rains. Keeping them on the dryer side will allow them to tolerate the cold winter nights we can experience in Southern California.
Bring in cold-sensitive, warm growing orchids (phals, paphs, tolumnias, most vandas and some warm growing cattleyas such as violacea, dowiana and their hybrids) to protect them from night temperatures below 50o. An excellent article on ‘Cold Tolerance of Orchids’ by Sue Bottom of the St. Augustine Orchid Society can be found in their October Newsletter (pgs. 9-11)
Cold tolerant orchids, including Odontoglossums, Miltonias, Pleurothallids, Masdevallias, and Draculas, will welcome the cooler weather and respond by initiating growth so continue to water and fertilize them during this period but also protect from freezing temps.
Fall/winter blooming Cattleyas and Cymbidiums are now in bud or bloom. Provide adequate water and fertilizer, but do so in the mornings so plants dry out before nightfall. Stake cymbidium spikes to guide inflorescences for support of buds and blooms.
Maintain good hygiene practices to minimize transmission of pests and viruses. Watch for fungus and bacterial rot in cold and wet weather.
More details on specific genera can be found on the AOS website