[header] How to grow biennial vegetables [title] Wait to plant until after the final frost to prevent seeding in the first year. [step] Biennials should be planted in the late spring or early summer to avoid early flowering from exposure to cold temperatures. If the plants flower during the first year, it is likely because they were exposed to frost. 
[substeps] While waiting to plant, store the vegetable seeds in bags in a warm, dry location. In colder climates, you can get a head start by planting the seeds indoors, and then moving them outside when the weather improves.