I haver a rather odd situation happening right now, and I am looking for some feedback on how long newly germinated seedlings can be kept in the dark at low temps before planting.
My scenario is that I have just started to get a few germinations in my petri dishes that are in my fridge (at 40 degrees). The seed casing has split and the tap root has just barely started to come out. My problem is, in about two weeks, I am going away for a week during which no one will be able to check on my seedlings for me. Normally, as soon as I see seed casings split I take my petri dishes out of the fridge and as soon as I see a tap root starting I pot them up. So, I have little experience with delaying removal from cold stratification and delaying planting. My question is…for how long can I leave these new germinations in the fridge without causing a problem for these new seedlings? Is 3 weeks too long? Will leaving them in the fridge actually “shut down” the germination that has already started to the point that when I do finally remove them they won’t grow any further?
I had thought that I was going to go ahead and pot them up now and then just put baggies over the pots to retain moisture in the pots while I was gone. I use grow lights so I was just going to leave the grow lights on while I was gone. Although, I am not sure I am entirely comfortable with that idea either.
Any thoughts or experience with this type of scenario?
I am a lazy grower so I often leave seedlings until enough have accumulated to bother with transplanting, rather than paying attention to one at a time. At that temp they grow quite slowly, but I regularly transplant out when they are 2 inch tall plus 2" root for a fraction of the seedlings. My losses are no worse for those than for ones where there is merely cracking of the achene and no root elongation at all (some of those latter may in fact be non-growers). See how they progress for a week and you can gauge how much they will grow in another week. Lowering the temp of the frig can help also.
I put all my seedlings in peat pots with germinating soil which are sitting in a tray of water under lights. You can put enough water in the tray to last a week easily. I have gone away for two weeks with no problem. I don’t worry about having to water them very often and I even put full strengh magnum gro fertilizer in the water with no problems whatsoever after a couple of weeks. In your case any size peat pots and any tray large enough to hold water would do just fine. Good luck.
Patrick
I’ve often left germinated seedlings in the fridge for several weeks or more. Based on my experience, if the root is just beginning to show now, they will be fine for another few weeks. Even in cases where I’ve left germinated seeds in the fridge (in the dark) too long and they have grown too leggy; I’ve had good luck growing them on by cutting the roots off, treating the stem with rooting hormone, and planting. I usually only leave 1 to 1.5 inches of stem attached to the cotyledons. Seedlings that I
Thanks everyone for the feedback. Much appreciated. I think I am going to let them go for another week and see how much they grow or don’t grow. If they seem to be barely inching forward in growth I’ll just leave them in the fridge and then pot them up when I get home. If they seem like they are growing quickly then I will try using the baggies over the top and maybe a skimming of water in the tray right before I leave (I use the 3x5 tree band pots in seedling trays).
Thanks again for the feedback. I’ve been growing seedlings for over 5 years now…but I’ve never even had to consider SLOWING germination before…LOL, so this was a completely new scenario for me.