Neves Azorean Red
Tomato (Beefsteak) in the UK

Beefsteaks are a bit hard, like I say, because they need a long, warm season here in the UK. You'll want to sow indoors, definitely, from March through to April. Get your seeds into small pots or trays, about 1 cm deep, in some good seed compost. They need warmth to get going, ideally 20-25°C, so a heated propagator or a warm spot with a grow light is just the ticket. Don't rush 'em, give them a good start.

Once your seedlings have their first proper leaves, carefully prick them out into individual 9cm pots. Keep them warm and in a sunny spot. Come late May, once all danger of frost is well and truly past – which for us up north is mid to late May, mind – start hardening them off. Plant them out into your greenhouse, or a very sheltered sunny spot on the plot, giving each plant about 60cm clearance. These get big, so good support from the off is crucial.