Bulbs Can’t Freeze

Freezing seem like as good enough topic as anything because that’s all we seem to have in the forecast.  This is like the third week of real winter temperatures and after a bunch of warm years it seems so…. endless.  Realistically three or four months of winter wouldn’t be anything surprising in this zone, so with two more months to go there is no reason to complain.  It’s just the warmer years of late had me kind of enjoying witch hazel in January and snowdrops throughout.  Toughen up I say!  Truthfully I should be grateful for the nice solid cold, and the way it freezes up the soil and tells the bulbs to hold on, don’t be fooled, February and March will be early enough to start your growing plans.

frozen colchicum bulb

Colchicum x byzantinum bulbs are big, and my soil is shallow, and often they just push themselves up and practically sit on top of the soil.  Obviously in this position and with temperatures down to 0F (-18C) the bulb and new growth will freeze

Some of the top spring disasters (off a quite lengthy list) have been the result of warm winters which bring things up way before their time.  Hellebores in particular must be an unusually optimistic plant which falls for this fake spring followed by a hard freeze every time, but snowdrops can be fooled as well.  Often I’m surprised by how well tender growth can survive brutal freezes but it’s not always a happy ending.  Right now a better gardener would be covering some of these goodies to keep the worst of the weather off of them.

snowdrops in the snow

We will see how well ‘Godfrey Owen’ tolerates the rest of winter after having already come nearly into bloom.  Tonight will be cold, next week looks colder.

I guess that brings me around to the title of this post.  I often see claims that hardy bulbs need to be protected from freezing, especially those in pots.  I disagree.  I used to pot up bulbs and throw them into an unheated shed where they would freeze solid for months without ill effect.  I’ve dropped bulbs in the fall and had them root into the surface, survive winter exposed and also do just fine.  There’s more to it of course but without exposing my own ignorance I’ll just point out a few ‘excepts’ which I’ve come across.  Bulbs need to begin rooting before they freeze.  Potted bulbs should be on the dry side before freezing.  Exposed pots which freeze and thaw repeatedly will suffer.  -and the one which I can’t figure out is that potted bulbs will rot when snow melts and then re-freezes on the surface of a pot of bulbs, especially later in the year.  My balcony gardening year was always off to a tragic start when a big pot full of tulip and crocus sprouts would all just stop growing after a cold spell hit with snow or rain freezing on top of the pot.  Weeks later I would finally give up and pull the still green and solid sprouts out, leaving a rotted bulb behind. 😦

Well that ended on a sad note.  If anyone has some thoughts on this let me know.  I find the easiest way around this is to just cover planted pots with autumn leaves and then uncover them as soon as temperatures warm, but you know how greedy I am with my autumn leaves!  Maybe a board on top to keep the snow and rain off would be good enough, I just have to remember to try that (again) and make a note of how it works out.

In the meantime stay warm and consider that (here at least) the daylength is getting longer by about two minutes each day and we’ve added about 30 minutes since the shortest day of the year.  I’m sure we’ll be in flip flops before you know it 😉