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From Flask to Pot

The time has come to deflask your babies. What do you have to do? This is one of the easiest steps in orchid growing. Many people spend considerable time and effort removing the last bit of agar from the roots, dipping the plants in damp-off preventing solution, and generally fussing over the babies. Our experience has been that they can be planted out directly from the flask with only a short rinse under the tap to remove the large chunks of medium still clinging to the roots.

Baby Paph. rothschildianums ready for action.

If the environment they are going into is very dry then you may wish to provide some method of increasing the humidity around the plants. The tops off of old juice or pop bottles may be used as a cloche if there is an opening to allow some air circulation. Changing the air is critical for baby orchids. The most frequent cause of death for small orchids is moisture on the leaves, especially at night. We always make certain that the plants do not have any moisture on their leaves in the afternoon and are dry by evening. Damp-off and bacterial infection are almost certain to destroy baby plants if their leaves are wet overnight.

A cloche.

A diffuse light position.

Young Phalaenopsis .

The best environment for young plants is moderately humid, bright and with a lot of air movement. We have found that newly deflasked seedlings can be placed directly in front of large fans in the greenhouse and not watered for three or four days( using dry seedling bark). They may wilt a bit but they do not suffer from any fungus or bacterial infections in the breaks or scrapes that occurred during deflasking\ planting. It gives injured tissue a chance to callus over or dry up.

Strong air movement may be a little too harsh for windowsill type setups with low humidity but strong air movement is always recommended providing 50% humidity can be maintained in the growing area.

Air movement is very important for young plants. The first thing that will happen as plantlets leave the 100% humidity of the flask will be the formation of a waxy cuticle on the leaves in order to slow evaporation from their unprotected surfaces. Vigorous air movement and slight water stress will speed up that process.

Plants need fairly strong, filtered light to supply the energy necessary for wax manufacture and to lay down an effective, new layer of insulating cuticle.

Non-sterile tubs containing plants saved from contaminated flasks They are growing in diffused light in the greenhouse

Potting medium is always an interesting discussion.

We have used sphagnum moss or seedling bark for freshly deflasked seedlings. Turface or any other inert material may also be used provided the plants receive supplemental fertilizer. Plants are put directly into a 2 1/4 inch pot which has been filled 1/2 full of white styrofoam peanuts. Pink and green peanuts contain chemicals plants do not like! The roots are then covered with dry seedling bark to the pot rim. Finally and most importantly two strips of cellophane tape are placed on either side of the seedling The tape stabilizes the medium. It won't wash out or move around when you water the pots. Humidity is also maintained around the roots and in the pot by the tape. We consider it to be an essential step in potting healthy seedlings.

Newly potted plants

Seedling bark

Pots taped up

Very small plants or protocorms may be maintained if they are provided with additional humidity. Use of a plastic cloche as already discussed is one option. Another is to place the plantlets into a closed environment such as the plastic food tubs used by grocery stores. These are used in the greenhouse for very small plants being rescued from contaminated flasks. Replating babies or protocorms from a contaminated flask onto new medium is fruitless. They can sometimes be saved by placing them in high humidity environments. Moss is a greater problem in the non-sterile tubs though. It can overgrow seedlings and smother them if not managed aggressively. Physan spray or a light dusting of composted sheep manure will retard moss growth significantly. The manure also serves as an excellent fertilizer.

Very little moisture is needed in these closed system environments and light levels should be quite low. Excess light can cause a heat build-up that cooks the plants since heat cannot escape when the top is on. A paper punch is used to create two ventilation holes in each lid.

View into a flask	Turface as a substrate	Relative size of plantlets Vs floor
	View into a Paphiopedilum flask

As the plants increase in size, they can be moved on up into larger pot sizes. We tend to push them into coarser grades of bark at the earliest opportunity. Open medium and frequent watering encourage vigorous root growth.

	Healthy babies moving up in pot size. These are potted into medium grade bark.
A group of young Paphiopedilums ready for potting upward.

Use the results of our growing experience or try new experiments of your own to come up with a system which works for you. Hopefully this information will save growers some of the losses that are inevitable when dealing with living organisms. Good luck and good growing. You can do it!

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