Ben Tirran
Blackcurrant in the UK

Blackcurrants are usually started from bare-root bushes, not seeds or plugs, you know. You can plant these from November right through to March, when the plant is dormant. Dig a decent hole, making sure you plant them deeper than they were in the nursery, about 5-10 cm deeper. This encourages new shoots from the base, giving you a stronger, more productive bush in the long run. Space them about 1.5 metres apart if you're putting in a row. They're hardy, so no need for a greenhouse or anything like that for planting out.

Once your bare-root bush is in, there's not much faffing about needed for "growing on" like you would with seedlings. Just make sure the soil is firmed around the roots. They don't need pricking out or hardening off, as they go straight into the ground. Blackcurrants are quite sturdy, so no real need for support unless your plot is particularly exposed to high winds. They can be grown in large containers if you're short on space, but a good deep pot is a must, like a half-barrel or something similar.