AOS News – May 2017

ORCHIDS Vol 86 No. 6 April

Top Dressing Your Orchids pg 264

AOS 2017-05 Top Dressing
Cypress mulch used as top dressing will provide a little bit of acidity to counter the effects of high alkalinity water as well as allow you to top-dress coarse potting mixes with timed-release fertilizer without having it wash through the pot.

RETAIN MOISTURE by placing a layer of sphagnum moss at the top of your pot. Newly emerging roots will jump for joy! Environment humidity will also increase.
PREVENT WASHOUT of your fine bark, soil-less or terrestrial mixes by adding a top dressing.
BUFFERS ROOT ZONE pH. Alkaline water? Consider adding acid-generating top dressings to keep your potting mix in the slightly acidic range which is optimal for nutrient availability.
ADD TIMED-RELEASE FERTILIZERS so that nutrients release and wash over your roots every time your water.
Ca & Mg SUPPLEMENTS such as: granular dolomitic lime, crushed oyster shell and steamed bone and fish meal provide essential nutrients. Be aware that they do increase root zone pH.
ORGANIC additives such as Alfalfa Meal increase the organic matter in your potting medium and stimulate microbial life around your orchid roots. It also contains trace minerals and trianconatol, a natural fatty acid growth stimulant. Fish meal is a slow release fertilizer. Kelp is rich in trace minerals, plant growth regulators, vitamins, hormones, amino acids, enzymes and chelated nutrients. (i.e. Purely Organic fertilizer contains alfalfa meal and kelp)

For new members, the American Orchid Society’s ORCHIDS magazine is a monthly must! When you subscribe to a digital or mailed copy, you are invited to view live streaming webinars. You can also view the archives. Visit

AOS Webinar 2017-05

AOS WEBINAR – Orchid Aquarium / Terrarium Culture
Thursday May 11, 2017 @5:30 PM – 6:30 PM PST
Members Only – Webinar Details PageRegistration Page

Join Daniel Geiger, Ph.D. Curator of Malacology at the Santa Barbara Museum of Natural History, California as he presents a fascinating talk on raising orchids in confined spaces, terrariums and aquariums.

– Krystal Goulart (VP & AOS Rep)