Hi MPG,
I raised my Asparagus seedlings in summer 2016 and overwintered them in an unheated greenhouse in pots. During this time they stayed green so I kept feeding and repotting. They built up over the Winter very well and at no stage went dormant. This speeded up their development and, having taken a small harvest this year, the plants have come on in leaps and bounds and I expect a cracking harvest next year.
BR
Neil
