Bernard, as with all bulbs you want to leave the leaves alone until they die back so the corms can gather energy from the sun and they will come back and possibly naturalize in your garden depending on where you are and your growing conditions. Once the leaves have died back then you can cut the old foliage down to the ground. A bulb fertilizer will help them grow better if you fertilize, I believe, after the blooms are done. Happy gardening!
Bernard, as with all bulbs you want to leave the leaves alone until they die back so the corms can gather energy from the sun and they will come back and possibly naturalize in your garden depending on where you are and your growing conditions. Once the leaves have died back then you can cut the old foliage down to the ground. A bulb fertilizer will help them grow better if you fertilize, I believe, after the blooms are done. Happy gardening!