Some of them.

Not really aside from the species bulbs in pots. Which plants are you asking about specifically Geraldine and welcome to GoY

Welcome from me too, like Louise - Ifeed some depends on the plants? poor soil plants in the rockery such as Dianthus I dont, but annuals such as Petunias every other week.

Some plants are hungry feeders - like roses and clematis. They need enriched soil to start off, then I feed them after I prune them with a handful of blood, fish and bone, after which they get a liquid feed once a month. All my container plants get a liquid feed too.