Settling in: the first 10 days of a plant that has travelled
The new Sonerila and Begonia arrive on Monday. What to do and — above all — what NOT to do in the first ten days: no repotting, no fertiliser, just steady humidity and indirect light.
A plant in transit spends two or three days in the dark, inside a box, unable to transpire and with the temperature doing as it pleases. When you open it you are not looking at a healthy plant: you are looking at a plant that has just stopped holding its breath. Everything you do in the following ten days decides whether it recovers quickly or takes two months.
The rule that covers everything: in the first ten days you improve nothing. You leave it alone.
On the first day you open the box and nothing more. Take the tissue off, check there are no rotting leaves touching others, and put the plant where it will live. Indirect light, away from radiators and draughts. Do not water straight away: push a finger into the substrate and feel. Nine times out of ten it is already damp, because I shipped it damp on purpose.
What NOT to do, in order of how much damage it does.
Do not repot. It is the commonest mistake and the most expensive. The roots are the organ that suffered most in transit, and repotting means breaking them again while the plant has no energy yet to rebuild them. The pot it arrives in is fine for at least a month. If the pot offends you, drop it inside a cover pot.
Do not feed. A stressed root system absorbs badly, and the fertiliser left in the substrate raises the salinity and burns the tips. The first feed comes when you see a new leaf, not before.
Do not move the plant around looking for the perfect spot. Every move is another light adaptation to start over. Pick a decent place on the first day and leave it there.
Do not cut off leaves that look ruined. Even a half-yellow leaf is still photosynthesising and sending sugars down to the roots. It comes off only when it is completely dry, or when it rots.
What to do instead
keep the humidity steady. Understorey tropicals come from an environment where the air sits between 70 and 85 per cent, and indoors in winter we are at 35. A glass cloche, a clear bag left open at the top, or simply a group of plants stood close together makes an enormous difference. What matters is that a little air moves, or the high humidity turns into mould.
What to expect, day by day
In the first three days one or two lower leaves may yellow: that is normal, the plant is reclaiming what it can from the old ones. Between the fifth and the seventh day turgor returns, which is to say the leaves stop looking tired. Between the tenth and the fifteenth you should see the first new movement: a tip, a rolled leaf getting ready to open.
When you should worry
if the stem goes soft and dark at the base, that is rot and it is the one real emergency. Take the plant out of the pot, cut above the soft part with a clean blade and root it again. If the leaves turn translucent and sticky you are watering too much. If the edges go brown and dry the air is too dry.
After ten days you can start behaving normally again: repot if it is needed, feed at half dose, move the plant to its final position. But move in stages, one thing at a time, so that if something goes wrong you know what it was.