Repotting

You should only repot orchids when you NEED to repot orchids. Many orchids resent the root disturbance that comes with repotting, so it is not a good idea to repot needlessly. The following reasons are the only times you should consider repotting : 1)The potting mix has broken down; 2)Your plant has a health problem, so the roots need to be examined; 3)The plant was accidentally dropped and got damaged or unpotted in the process; 4)The plant has outgrown it’s pot. (“Outgrown” orchids like to be tight in their pots and thrive best when this is the case. In fact, Cattleya alliance plants actually bloom best when they are 1 or 2 growths off the edge of the pot, so repotting them sooner deprives you of a nice display of flowers.)

When to Repot

Consider the growth habits and culture of your orchids. The optimal time to repot is after the plant has bloomed and is beginning a new growth cycle. The emergence of a new leaf, new roots, or a new pseudobulb signals this time.

Early Spring

This is the best time to repot most orchids as the days are getting longer; you see new growth; and they are no longer blooming. It the time to check your Brassavola (Winter – Spring) , Cattleya(Spring/Fall), Catasetums, Cymbidiums, Dendrobiums, Epidendrums, Encyclia, Ludisia(Winter-Spring), Masdevallia, Oncidiums, Paphiopedilum, Phalaenopsis (Spring-Summer), Sophronitis, Stanhopeas (Spring/Fall)

Repot in Fall

Doritaenopsis (Fall-Winter), Miltonia, Miltoniopsis, and Vanda.

Other Times Repotting May Be Necessary

Repotting may be required if an orchid is infested with bugs. If bugs keep recurring it is sometimes because they have taken their operations underground and are munching on the roots or in the media. Removing all of the old mix, carefully cleaning and examining the roots and repotting in fresh mix is often a critical step in eradicating a persistent pest issue.

Pot Size

Should be selected according to the size of your plant’s root mass and growth habit. When potting epiphytes (tree-dwellers), these are lateral or shallow rooters, so choose pots that are not as deep as they are wide. When potting terrestrial types (ground dwellers), they will want to root deeply, so choose pots that are deeper than they are wide. If the current pot is the right size, then you should clean it and re-use it!

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From the April 2013 issue of Orchids Magazine
Prepared by the AOS Education Committee with Photographs by Greg Allikas

Everything I have learned about repotting orchids (and haven’t managed to forget)

By Bob Findlay

Step 1

Pick plant for repotting, remove and secure tag (photo 1). I this case I have chosen a Miltoniopsis – theses should be repotted yearly and this one was last repotted 2/19. Remember to practice good hygiene – sterilize tools and wash hands between plants. I have taken to using paper to catch old media (rather than a tub) and change after each plant.

Step 2

Remove plant from pot (photo 2). Grasp plant and pull. If plant is really stuck in the pot running an old bread knife along the pot can help (photo 3). Now and throughout take care not to damage new growths. When it does happen, don’t fret too much – while this will set the plant back, they are plants and animals eat plants all the time – they have evolved contingency plans.

Step 5

Chose the correct pot. This plant could either go back in the same pot (2.5 inch aircone; photo 10 top) or be moved up to the next size (3 inch aircone; photo 10 bottom). If there was any indication that this plant was struggling I would have left it in the 2.5” pot, but since the root mass increased since last potting and there are three new growths putting out roots, I moved it up to the 3” pot. If you have any doubt, put it in the smallest pot that the roots will go into (one of the best ways to kill an orchid is to put it in a pot too big for the root mass – remember the pot is for the roots, not the green stuff).

Step 6

Chose the correct medium (for: (1) the plant (read up on line); (2) your growing conditions; and (3) your watering habits (do you tend to water too frequently or not frequently enough)). I use a fine fir bark mix (photo 11 – I mix this myself – 3 parts fir bark, 2 parts course sponge rock (not perlite – too fine) and 1 part fine horticultural charcoal).

Step 7

Position the plant as far down in the pot as possible and add media (photo 12). Since the plant is growing in 3 directions, I positioned it in the center of the pot. If it were growing in 1 directions, I would but the old portion of the plant hard against one side.

Step 8

Using your potting tool, work the media down around the roots (this is the most critical part of the process). Hold the plant in one hand and wiggle the potting tool back and forth, and up and down to help the media move into the center of the pot (above video). If you watch the video carefully you will see that the media was at top of the pot and all but disappears as it is moved down and around the roots. Once you have worked all the media into the roots, add more media and while applying gentle upward pressure on the plant simultaneously work more media downward and the plant upward until the pseudobulbs reach the top of the pot and you can no longer get any more media into the pot (it may take 4 or 5 additions of media to fill the pot).

The goal is to spread the roots throughout the pot (top to bottom and side to side) and to firmly affix the plant in the pot.

Top off the pot and gently compress the media with your fingers. It should look like photo 13. Note I am holding the plant by the leaves – this is a good check that you have firmly established the plant in the pot. You can pick the plant up by the leaves and have the pot and media come with it (this works with plastic pots and fir-based medium; clay pots – likely not!).

Step 9

Update your tags (photo 14). I like to note divisions, results of testing (the OK 2020 denotes negative for viruses) and the date of repotting (5/20).

Step 10

Return tags to repotted orchid (no one wants to make an orphan).