As soon as seedlings can be handled they should be transplanted to larger pots and kept in a sunny area, such as a window, florida room or even green house if available. Optimal Temperatures of 60�F - 70� F days and 50�F-60� F nights.
Come Spring you should have suitable seedlings equal to about 2/3 of the seeds you planted. I generally anticipate that 1/3 will never germinate or will produce inferior seedlings not worth wasting valuable garden space on.
Before transplanting them into your garden, a brief hardening off period is advisable.
At maturity they should reach 3 -4 feet in height with a spread of up to 6 feet so be sure to leave ample space for them to grow when you transplant them outdoors. In Zones 7 and above, plant the artichokes to the side so that the more frequent planting of annual vegetables won't disturb them. Space the artichoke plants at 4'-6' feet within the row with 6 to 8 feet between the rows.
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