June To Do List


  • 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.
  • It is desirable to remove spikes from bloomed-out plants since senescing spikes drain energy from the plant and attract pests. This is particularly true for oncidiums.
  • Some hobbyists choose to cut phalaenopsis spikes halfway to induce them to re-bloom in the summer; however, this practice will usually result in only a few more flowers. Optimal blooming is achieved by removing the spike after blooming and allowing the plant to regain energy over the summer, followed by inducing spike formation in the fall.
  • More details on specific genera can be found on the AOS website

Indoors and Greenhouse

  • Address higher light levels by adding shade cloth or painting with shading compound to avoid burning sensitive plants. 
  • Carefully monitor greenhouse temperatures as higher summer temperatures can easily cook plants. Make sure fans and automatic vents are in good working order.
  • Continue to provide good air circulation for indoor plants to discourage diseases and pests such as mealy bugs and scale. Treat early to avoid spreading to other plants. More info on pests and diseases can be found at the AOS website.
  • Increase watering and fertilizer to accommodate growth during this period. Avoid over fertilizing to minimize root damage and growth of soft growths. Keep to one half to one fourth the recommended amount on the package.
  • If you grow your plants inside and have outdoor growing space, move your plants outside for the warm season. Do this especially if your plants are crowded together or your hanging plants drip on the plants below when you water. The humidity and larger temperature differential between day and night are beneficial for your plants.


  • Continue to monitor and control snails, slugs and pests during warm weather. They can do considerable damage to plants in short order.
  • Cattleyas, oncidiums, and summer blooming cymbidiums should in full bloom and/or producing new root and bulb growth.  Increase watering frequency and fertilizer as new growth is observed and repot as appropriate. 
  • Neofinetias can be repotted at this time especially if they are maintained in sphagnum moss.
  • Cymbidiums can still be repotted and divided at this time, if needed. You should allow at least 3 growing pseudobulbs and no more than 2 back bulbs per pot.
  • Catasetums are ready to begin watering and fertilizing now that roots are 3-5 inches long.  Give them warm temperature, high light and fertilizer at each watering to take full advantage of the growing season.  You will be rewarded by rapid growth all summer, followed by beautiful blooms in the fall and winter.   More details on culture can be found on Fred Clarke’s website link:  Fred Clarke’s website


The monthly To Do list is a collaboration of several POS members. We appreciate any and all comments, suggestions, and feedback on our new feature. Please send them to newsletter@palomarorchid.org!