[barbarella]

When is the best time to put rhubarb crowns in?  If winter is okay, should I wait for a milder spell as freezing weather is forecast?  I am just digging up some old chrysanthemum plants which I inherited on my allotment and which I have been told have been there for years and I want to put rhubarb in its place.  I haven't got a lot of space as I only have a 1/4 sized plot.  Would one crown be enough for the occasional rhubarb crumble or should I plant at least two (maybe different varieties)?

[mumofstig]

You can plant anytime, they're tough as old boots.
IMO If you plant only 1 'bought in' crown it will take a couple of years to give a good picking, but will then romp away.
So if you need the harvest quickly for the short term, I would plant 2. Then in a the long term if you get too much.............you know what to do...give it to someone else

If someone is giving you a large root, say, from another allotment...I'd just stick with that
Hope this makes sense

[barbarella]

You can plant anytime, they're tough as old boots.

That's really useful, thank you.  I have been offered rhubarb crowns in the past, but just when I want some there is hardly anyone about on the allotment to offer me any .   However, I have a good idea I will be getting a few garden tokens for Christmas and I am looking forward to a mooch about the garden centre in January. 

[Babstreefern]

Even though its going to be freezing, the best time to plant it is after the freeze, it does it more good than harm to do this.  Then plant it with some good compost/manure.

[Trillium]

If its potted and growing, you can plant it any time. Its just the bare roots that are a bit fussy and prefer a dormant time to be dug up and replanted. As mentioned, give the soil loads of nutrients before planting as it'll be there a long time and will yield fab crops for you.