Houseplants

Bringing plants inside — without the pests

Every houseplant that summered on the deck comes back inside carrying passengers — that’s the assumption to start from. The goal of move-in week isn’t to hope your plants are clean; it’s to make them prove it before they rejoin the ones that never left.

Start earlier than feels necessary

The move starts when nights begin dipping into the low 50s — in the north metro that’s usually mid-September, a solid month before frost threatens. Two reasons to jump early. Tropical plants sulk hard below 50° even without frost. And the gap between outdoor light and your living room is enormous; a plant moved in gentle September light adjusts, while one yanked inside the night of a freeze warning drops leaves like it’s insulted.

Inspect, soak, shower

Before anything crosses the threshold, work through it outside. Look at leaf undersides, stem joints, the rim under the pot lip, and the drainage hole — that’s where aphids, spider mites, scale and egg masses actually sit. Soak the whole pot to the rim in a tub of plain water for fifteen minutes: anything living in the soil — ants, sowbugs, earthworms, fungus gnat larvae — comes up for air and floats out, which beats discovering them in the kitchen in November. Shower the foliage off with a hose on gentle pressure, tops and undersides. If you found real trouble, a plain insecticidal soap, coating the undersides until dripping, is as far as we’d go — repeated a week apart, it handles the soft-bodied culprits.

Then quarantine like you mean it

The returning plants live in their own room — or at minimum their own corner, not touching resident plants — for two weeks. Most hitchhikers reveal themselves in that window. A couple of yellow sticky traps stuck in the pots make the invisible visible: if the traps stay clean for two weeks, the plant graduates. This is also the moment to skip the repot. Fall repotting stacks a second stress on top of the light change; unless something is root-bound to the point of strangling, save it for spring.

Expect a sulk, not a death

Even a perfectly handled plant often sheds leaves in weeks two and three — a ficus can drop a third of its canopy. That’s not pests and not your watering; it’s the plant swapping sun leaves for shade leaves that work indoors. Keep it in your brightest window, water less than you did outside, and wait. New growth sized for the indoors follows. (What winter itself does to them is its own guide.)