Hi Luke. You can carry on picking individual leaves of collard greens from your plants for as long as the plant keeps producing them. When the plants eventually bolts (flowers) then new leaf production ceases. Collards are a cool-season crop, so if you have very hot summers then sowing new plants in late summer for fall planting and winter harvesting is a good idea. Otherwise, in more northern gardens, you can sow from early summer to plant out in late summer/early fall for harvesting fresh leaves all fall and into early winter.
Hi Luke. You can carry on picking individual leaves of collard greens from your plants for as long as the plant keeps producing them. When the plants eventually bolts (flowers) then new leaf production ceases. Collards are a cool-season crop, so if you have very hot summers then sowing new plants in late summer for fall planting and winter harvesting is a good idea. Otherwise, in more northern gardens, you can sow from early summer to plant out in late summer/early fall for harvesting fresh leaves all fall and into early winter.