The biggest issues are light and temperature. Unless you have grow lights, if you plant too early you will end up with very tall plants with huge distances between flower trusses, leading to weak stemmed plants and a reduced crop because you will have to stop them off when they get too tall. You will also find that they become impossible to move or plant out without breaking them or knocking off developing fruit. I therefore sow several lots of tomatoes at different times, depending on where they are eventually going to live:
January - 2 Shirley seeds (sown yesterday) which will start under lights and move to my sitting room windowsill when they get too tall (about a foot + 3 litre pot). These will produce 2 or 3 trusses and some sideshoots fro growing on later.
February - 6 more Shirley, again grown under lights until too big. 5 of these will live on the sitting room windowsill in 3 litre pots, providing 2-3 trusses. Lower sideshoots will be left on both sets of Shirley to provide a second main stem later in the year and hopefully fruit into January (I am harvesting these from last year now). The remaining plant (insurance) goes to my friend's unheated greenhouse when it gets too big for the lights, where in recent years it has survived, but might not in a cold spring.
February - 4 Balconi (2 red, 2 yellow) under lights until they get too big. These rarely grow more than a couple of feet high and live on my east facing spare bedroom windowsill in 3 litre pots until the first flush of fruit is finished (usually June) and are then planted out into bigger pots outside where they continue to fruit until the first frost or the blight arrives, whichever is earlier (usually October-November here).
April - main sowing for plants to eventually go outside and in my friend's unheated greenhouse (last year I did this on 22nd April). Varieties this year will include Sungold, Ferline, Crimson Crush, Mountain Magic, Roma, Brandy Boy and Garden Pearl. Again grown under lights, but in 9cm pots, moved to greenhouse and growhouse when conditions are suitable and planted out when hardened off.
March & April - any decent sideshoots on the indoor Shirley plants are potted up to add to the greenhouse and outdoor plants.
January - 2 Shirley seeds (sown yesterday) which will start under lights and move to my sitting room windowsill when they get too tall (about a foot + 3 litre pot). These will produce 2 or 3 trusses and some sideshoots fro growing on later.
February - 6 more Shirley, again grown under lights until too big. 5 of these will live on the sitting room windowsill in 3 litre pots, providing 2-3 trusses. Lower sideshoots will be left on both sets of Shirley to provide a second main stem later in the year and hopefully fruit into January (I am harvesting these from last year now). The remaining plant (insurance) goes to my friend's unheated greenhouse when it gets too big for the lights, where in recent years it has survived, but might not in a cold spring.
February - 4 Balconi (2 red, 2 yellow) under lights until they get too big. These rarely grow more than a couple of feet high and live on my east facing spare bedroom windowsill in 3 litre pots until the first flush of fruit is finished (usually June) and are then planted out into bigger pots outside where they continue to fruit until the first frost or the blight arrives, whichever is earlier (usually October-November here).
April - main sowing for plants to eventually go outside and in my friend's unheated greenhouse (last year I did this on 22nd April). Varieties this year will include Sungold, Ferline, Crimson Crush, Mountain Magic, Roma, Brandy Boy and Garden Pearl. Again grown under lights, but in 9cm pots, moved to greenhouse and growhouse when conditions are suitable and planted out when hardened off.
March & April - any decent sideshoots on the indoor Shirley plants are potted up to add to the greenhouse and outdoor plants.
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