Care guides

Almost every plant that dies indoors drowns. Roots need air as much as water, and a pot that never dries is a pot that rots from the bottom while the leaves still look fine.

Push a finger in. Two centimetres dry means water; damp means wait. That test beats any schedule, which is why our reminders hang off the window — a south window in July and the same window in January are not the same plant-drying machine.

Roots out of the drainage hole, or water running straight through without wetting anything: those are the two signs. Not the calendar.

Go one size up, no more — a plant in an enormous pot sits in wet soil it cannot reach. Use a mix with bark or perlite in it so there is air around the roots, and do not water for a couple of days afterwards.

Spring is easiest because the plant is already growing. Repotting a plant in December is not fatal, it is just slower to recover.

Four questions and someone who actually grows these tells you what will live in your room. It works for a plant you bought somewhere else too — we are not selling yet, so there is nothing to sell you at the end of it.