I was a total failure at growing bulb sized onions for many years. That changed when I learned to plant my seedlings in January instead of April and to plant them very shallow. I now plant them about 1/2" deep. The past two years have rewarded me with very large sweet onion bulbs. I grew so many this year, we didn't harvest or eat all of them before the tops died, fell over, and disappeared. Now when I need a couple of onions, I use my garden spade, turn some soil over; and harvest them as needed.
I expected them to remain hidden beneath the soil until I turn the garden soil over in the winter. They instead are sending new green leaves up in the hottest part of the summer. What is the life cycle of the onions producing new leaves now? Will they continue growing depleting the bulb, or will they grow into the fall, pause for the winter; and produce larger bulbs next spring?