Q.Onions and Carrots
I have planted my first garden this year and so far it has really taken off! I do have a few questions about my carrots and onions. I am not sure when I should harvest them. The carrots leaves are really green and look great and so do the onions. The onions tops are starting to fall over and they are pretty tall. I planted them the 2nd week of April.

Certified GKH Gardening Expert
With both carrots and onions, you can judge if they are ready for harvesting by digging out a little next to where the root is and see how big the root has gotten. If they are an acceptable size, then you can harvest.
With the onions though, once those leaves die (turn yellow) the bulbs will not get bigger, so you have to harvest at that time - regardless of size.