I bought a set of ‘saucers’ for my 12 inch tomato pots and with the hot summer this was a great way to know when to water the plants. It ensured that the roots never dried out and I put the feed in at the top of the pot, feeding a small amount every day.
It worked an absolute treat and someone I knew also had excellent results with the ‘quad grow’ system which uses the same principle but has a cover over the reservoir.