In Vitro Plantlet Instructions

Thanks for buying in vitro plantlets from Cultivariable.  Please read these instructions before opening your plantlets.  Removing your plantlets from the tubes and preparing them to be transplanted outdoors is not a difficult procedure, but it is also not a forgiving one.  Your plantlets have lived their entire lives in an ideal environment.  They have experienced 100% humidity, abundant nutrients, and no environmental stress, pests, or diseases.  Removing them from that ideal environment is a shock and the goal is to minimize that shock.

You don’t need to be in a hurry.  In fact, I recommend waiting three days before you remove them.  They have been in total darkness in the shipping box for a few days and it will help them to get some light.  There is a sufficient level of nutrients in each tube for the plantlet to survive at least another month and much longer in many cases.  Even if the plantlet grows up against the top of the tube, that is not a problem.  Keep your plantlets in the light, preferably some indirect sunlight, but normal indoor light is usually fine.  Do not place them in direct sun, like on a window sill, because you risk cooking them in the tubes.  Do not remove the wrapping on the tube until you are ready to transplant.  The wrapping is not plastic, but a paraffin wax product that allows for gas exchange while keeping out insects and most microorganisms.

For each plantlet, you will need one small pot, fresh potting soil, and a plastic bag large enough to fit over the pot.  You should also have a grow light or a location with good natural light where you will grow your potted plantlets for a few weeks.

I recommend that you do not transplant all of your plantlets at once, particularly if you don’t have experience.  I would divide them up over several days.

When you are ready, fill a pot with potting soil, tamp it down a little, and then give it an hour to soak up as much water as it can.  Put the pot on a surface where it can drain freely, like a nursery tray.  Now, take the tube that you intend to plant and push it into the soil so that the level of the agar in the tube is about 1/2 inch below the level of the soil.  Remove the tube and you now have a planting hole.  In the box with your plantlets, you should have found a disposable spatula.  The wide end of the spatula will allow you to remove the plantlet, hopefully with its agar substrate intact.  Remove the wrap from the tube and remove the cap.  Work the spatula around the inside of the tube and then use it to scoop out the plantlet.  You should then be able to slide the plantlet along with its agar blob right into the hole that you made.  The plantlet should be a little bit deeper than it was in the tube.  You want the agar to be covered by about 1/2 inch of soil.  Backfill the hole and level out the soil.  Now, take your plastic bag and cover the pot.  The saturated soil and the plastic bag provide the 100% humidity environment that the plantlet is accustomed to.  Keep the plantlet under lights or in natural light for at least 12 hours per day, but preferably 16 hours.

We now begin the process of hardening off the plantlet.  Leave it alone for two days.  On the third day, poke two holes about 1/4″ inch diameter in the bag.  A pencil or pen will do a fine job.  Add two more holes each day until there are ten holes in the bag.  (That makes a full week.)  The next day, remove the bag.  Observe the plantlet for signs of distress.  Most of the time it will be fine, but if it wilts, put the bag back on for a couple days and try again.  Don’t water the pots until the soil is pretty dry and always water from the bottom.  Continue to grow the plant indoors until it is 3-4 inches tall.  At that point, it is ready to be acclimated to the outdoors and transplanted to its final location as you would for any seedling.  Alternatively, you can continue to grow the plantlets in pots to maturity in order to harvest a crop of minitubers which can be planted directly in the garden the next year.

Common Problems

Either the agar or the plantlet came loose and moved in the tube

This is usually not a big deal.  If you have a dislodged plantlet, make that the one that you start with.  If it got jammed up and the stem bent or broke, it will usually still survive.  Just transplant it as best you can and give it some extra time under the plastic bag if it grows slowly.  If the plantlet broke off from the agar, transplant it alone.  Even if it lost its roots, it will usually be OK.  Just bury it about halfway up the stem and treat it like any other plantlet.

Fungi or bacteria are growing on the agar

When shipped, plantlets are subjected to changes in air pressure that can force bacteria or fungi into the tubes.  You might notice it beginning to grow after you receive the tubes.  This is rarely a problem since you will be transplanting the plantlets soon anyway.  Start with any that are contaminated.  Once you remove the plantlets from the tubes, the contaminating organisms will no longer have an ideal environment and will quickly die.

I accidentally chopped the agar into pieces with the spatula

It happens.  It is easier when you can extract one clean piece, but sometimes it just doesn’t want to cooperate.  Scoop what you can into the planting hole.  All that really matters is that you get the plantlet in there.

There are dead leaves on the plantlet

Shipping is a stressful process for the plantlets and sometimes they lose a few leaves.  As long as the stem is green and there are green leaves at the top, it is nothing to worry about.