Answer: Broccoli is a cool-season vegetable and mature plants can sometimes withstand temperatures into the 20s (F). You could try protecting from frosts in the evening and then removing the covering during the day. Use burlap, fabric, old sheets, blankets, etc., or purchase frost cloth from your nursery. Don't use plastic, and if possible, create a framework to drape it over so the cloth doesn't touch the plant. The cloth should extend to the ground, helping trap rising heat. Put the cloth on at sunset and remove in the morning. I hope this info helps and good luck prolonging your crop!
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