Sow about 25% more seeds than you want plants, to allow for some losses and so you can select the strongest seedlings.
You will need some clean seed trays. Those with individual cells work well, but you can also use suitable food packaging if you make sure there are holes for drainage. The trays need to be at least 3cm deep. Fill them with good quality seed compost – look out for Gardening Which Best Buys (and Don’t Buys!) Make sure the surface is level and firm. Sow the seeds about 3cm apart and cover with about 4mm of compost. Water them using a watering can with a fine rose. Cover with clear plastic or a sheet of glass. Put them somewhere warm to germinate: 20° - 25°C is ideal. After about 5 - 7 days the seeds will have started to germinate. They must be uncovered immediately and put somewhere with plenty of light, but still ideally 20°C (minimum 16°C).
It may be necessary to spray the seedlings with a fine mist to help the emerging seedlings shed their seed coats.
Did You Know?
British tomato growers wash 4 million m2 of windows a year, that’s washing London’s Iconic Shard, 71 times a year.