Direct seeding is possible but I would not reccomend it. Another uption is the cold frame. I start all my brassicas this way. They don't need a lot of heat. Yhis one is home made with framing timbers and a glass pane froma storm door. Starts roughly a hundred plants.
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check out the winter sowing forum on GW. It may be your answer instead of trying to direct sow broccli. Enjoy!!

Alberta

Info from THE KITCHEN GARDEN GROWERS' GUIDE (Amazon)

Broccoli:
Germination soil temperature: 50°-85°F, optimum 77°F
Days to germination: 7-10
Sow indoors: 6-8 weeks before last frost
Soil pH: 6.0-6.8
Growing soil temperature: 65°-75°F
Spacing of plants: 14-18 inches in all directions
Soil prepartation: Broccoli prefers humus rich, moist well-drained soil. Early season crops do best in sandy loam, loam or silt loam. Change planting location annually to avoid soil nitrogen depletion. Add compost to soil before planting. Apply two light application of blood and bone meal, or liquid fertilizer during the growing season.

Here is a link that might be useful: HarvestToTable.com

I live in South Florida. Set the broccoli plants in pots and then just threw some on the beds. The ones on the beds gave better results. (Just my experience). Currently they are about 8" tall and I have much more than I expected

Steve,
Here in central In. I sow seeds in plastic pots about the 22nd of March and plan to transplant them out on the 15th of April...weather permitting. the worst thing for broccoli is to leave them in pots too long or if direct seeded , to not thin them early enough.

They can be direct seeded about the 17th of April. A strip of clear plastic over the soil until the seeds first start to coming up will help greatly and it also keeps cold rains off. The plastic is optional and MUST be removed as soon as any seeds come up.

Broccoli needs about 24 inches or so between plants. Several plants grown in a group is good as the plants will shade the soil better.

So I have a question for the experts. My last frost is mid-April (Wilmington, DE is April 10, Williamsport, PA is April 30)...so I'm figuring Havertown is mid-April since we're about 15 miles out of Wilmington...

ANYHOW...I want to start my broccoli indoors and then transplant outside. My question is....can I transplant earlier than my last frost date IF I use a coldframe over it? I have panes of glass that I could essentially put over my raised beds to make a makeshift coldframe.

Thoughts? I'd like to get them in the ground mid-end of March to get a 2-4 week jump on the grow season.

Thanks in advance,

Pam
Havertown, PA

Last average frost daye here is April 15. I seeds February 1 and start transplanting around the spring equinox. Seems to work best for me. Although hardened broccoli and cauliflower will tolerate temps in the mid twenties, They tend to button if thier growth cycle is interupted
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