If I buy a large-ish lavender (in a 5 litre pot) could I divide it in two?
If so, when is the optimum time to do this?
I don't think so. I thought you took cuttings from lavender but I may be wrong.
I think August is the time for cuttings so not long to wait.
Some of these big pots of plants that come in from holland usually have between 3 and five seperate plants in a pot. They get more money for them that way by kidding the buyer they have a large mature plant. Check to see if yours is one of them, you can then seperate them and bring them on in different pots to put out next year.
Would you care to try this link.
http://www.rhs.org.uk/advice/profiles0804/lavenderrosemarycuttings.asp
Seems to be the way of doing these.
Thanks all.