I've been gardening for years but only just got into fruit & veg so need to ask a bit of a silly question.
This year my kind neighbour gave me a few onion & garlic sets & seed potatoes which he had left over. They were put in in March & are now all romping away. The potatoes are in a couple of purpose made bags & the compost has been up to the top for a few weeks & the foliage is about 2' above this.
Silly question is... how do I know when to harvest? Do I have to lift the plants to find out if they're ready or are there some tell tale signs with the foliage?