PROTECTING BEGONIA TUBERS FOR OVERWINTERING

Good grief, it's cold out there today.  I went outside into my little garden and removed the last of the hosta leaves which had died back and shrivelled up.  My hands were freezing.  I noticed, while removing the hosta leaves, that there were tiny 'spears' of next year's leaves just poking up ever-so-slightly out of the surface gravel.  I quickly covered them up.  It's not time for them to be so brave, winter is coming and this weekend we have been forecast some wintery conditions here in the north of England, although they are speaking of rain and wind (bit like summer really) and low temperatures, not snow.  It is time for the tuberous begonias to be protected and overwintered before I forget and damage is done.  I've grown the begonias in individual pots this summer and have allowed the stems and leaves to die back somewhat as I understand that the leaves feed the tubers (just as daffodil leaves feed the bulbs).  Most of the stems snapped off by themselves when I moved the pots which indicated to me that they were ready to be dried and store.  Remember, I am not gardening expert and I just find my own way by trial and error. 

Flower-heavy tuberous begonia (standing on a stack of terracotta pots)



The images below show begonia tubers that I have successfully overwintered for a few years now and they do grow to be whoppers the size of which you rarely, if ever, would see in a gardening centre.  I must be doing something right.  Right?

Giant begonia tuber filling the palm of my hand

Begonia tubers drying out a little in the sunshine in preparation for overwintering

Last year I stored my cleaned-up tubers in individual pots of vermiculite mixed with compost in the mini-greenhouse.  I like to keep the tubers separate from each other so that if the rot does set into one, the rest are not contaminated.  This year I am not erecting the little greenhouse but instead I have the garden room.  I planned to keep the tubers in there, tucked out of the way in a corner, in their pots of vermiculite and compost, inside a bag of gardening fleece,  However, as I seem to have no vermiculite, I'm simply going to store them in dried-out compost.  You'll know next year how that works out. 








I know the RHS recommend that you give begonia tubers a little water now and then to stop them drying out completely but, to be honest, I cannot be bothered faffing around with such stuff during winter and, dare I say, I'm not sure it's altogether a good idea if you don't plan to keep checking on them.  I'm no winter gardener.  I hibernate.  So the tubers will just have to do or die.  So far they have done well.

Overwintering begonias - RHS (external link)

• Tuberous begonias need to be lifted before the first frosts. The leaves will begin to yellow naturally at which time watering should be reduced. The dry tubers should be stored in barely moist soil or sand in a frost-free shed, ideally at 7°C (45°F), and watered occasionally to prevent shrivelling 
  
  
• The tubers of Begonia ‘Million Kisses’ may be small at the end of the first season but may then over-winter, however most gardeners replace their plants each year

Note, there is some health concern about vermiculite (Wiki link).  If you decide to use it, best to take care and not inhale it then, just in case, but check the link for further information. 




This is a link to another website about storing begonia tubers.  You will see that there is different advice there on how to store the tubers over winter.  Really, in gardening it's often a way of just finding what works for you and your plants as often gardens, soil, weather conditions, etc can vary so greatly.  http://www.bradsbegoniaworld.com/tuber.htm










Hosta 'Sagai' leaf dying back in glorious autumn colours.

The pelargoniums are in the unheated garden room and very happy so far, still in flower, healthy green leaves.  I cover them with fleece at night for a bit of added protection, just in case.  During the day I ensure that the blinds are up and they get plenty of light.  The little bay plant (laurus nobilis) is with them.