I'm not an expert. I try but probably do many things wrong. That said, I am trying cabbages. I live in zone 5, with a short growing season. I started cabbages indoors in April from seeds. They did well and I put them outside in may/June when they were established and had many big leaves. It is now September. They are growing tall and still producing leaves but only now beginning to ball up into a head. If I wait it out, will they continue to form heads as the days get shorter? What can I do differently to make them form up faster? The picture shows one plant which is around 12 inches tall. It seems to be balling up near the top.