Most likely your soil is loaded with nitrogen (great for lush green showy growth) and poor in phosphorus and potassium. It's a very common issue when using "premium" bagged potting compound.
You can plant cabbages (including Brussels sprouts, kale, pak choi, cauliflowers etc) to use up the excess nitrogen during the cold season, then start over with a more production-geared fertilization next Spring and then shift over to a nitrogen-free fertilizer when plants are mature to stimulate production, otherwise most plants will happily lap up the extra nitrogen, grow like crazy and leave you with next to nothing to eat.
