Orchids and flowering plants
Give flowering plants a generic house plant fertiliser every two weeks in spring, then change to a weekly feed that is rich in potassium in the run up to flowering. Tomato fertilisers contain extra potassium, but are often too strong for house plants, so dilute by half the recommended dose. Orchids do not appreciate heavy doses of fertiliser and can be killed by too much, so feed weekly with a generic house plant fertiliser diluted to half or even quarter strength. If using commercially available orchid fertilisers, follow the dosage instructions on the pack.