Late September in the Hill Country is deceptive. The afternoons are still running in the nineties, so it does not feel like autumn, but the days are shortening fast and your houseplants have already noticed. What you do over the next six weeks decides whether they coast through winter or spend it slowly declining.
Here is the sequence we follow in the greenhouse, and what it means for plants in a Boerne or San Antonio house.
Now: cut the watering back before the plant asks
Shorter days mean slower growth, and slower growth means less water used. If you keep to a summer schedule into October, the soil stays wet longer than the roots want and you get rot in a plant that was thriving a month ago.
Stop watering on a schedule entirely. Lift the pot instead. Light means dry, heavy means wait. A pothos that wanted water every four days in August might want it every ten by November.
Now: stop feeding
Most houseplants slow down or stop growing between November and February. Fertiliser they cannot use becomes salt in the soil, and we already have enough of that problem from the tap water. Give a final half-strength feed in early October and then leave it until you see new growth in spring.
Now: bring anything outdoors back in, and check it first
Plants that summered on a porch need to come inside before night temperatures start dropping into the fifties. Before they do, inspect them properly — undersides of leaves, leaf joints, the soil surface. Spider mites, mealybugs and scale ride indoors on porch plants every single autumn and then spread to the whole collection over winter.
Treat anything suspicious and keep new arrivals separated from the rest for two weeks. It is a nuisance. It is much less of a nuisance than a January mealybug outbreak.
October: move plants toward the light, not away from it
The brutal west window that scorched leaves in July becomes genuinely useful in November, when the sun sits lower and weaker. Plants you pulled back from the glass in summer can move closer again. This is the one seasonal adjustment most people forget, and it is free.
November: watch the heating vents
When the heat comes on, indoor humidity drops even lower than it does under summer AC — sometimes into the twenties. A plant sitting in the path of a heating vent is being dried out from two directions at once.
Move plants off vents. Group them together so they share transpired moisture. A pebble tray helps the thin-leaved ones. If you own a humidifier, the plants benefit as much as you do.
The cold snap: have a plan before the forecast
We are zone 8b, which sounds mild until it is not. February 2021 took temperatures into the single digits and killed a great many plants that had lived outside happily for years. Even a normal winter here delivers a handful of hard freezes.
- Anything tropical comes inside for the duration, not just overnight.
- Keep plants away from window glass on freezing nights — a leaf touching cold glass will get damaged even in a warm room.
- Do not water immediately before a cold snap. Wet roots plus cold is far worse than dry roots plus cold.
- If a plant does get frozen, wait before you cut. Damage takes a week or two to fully show, and pruning early often removes wood that would have recovered.
What this means if you are buying plants right now
Autumn is genuinely a good time to buy. The plant establishes through the cool months without summer heat stress, and it is settled and ready when growth restarts in spring.
It is also the point in the year where local pickup earns its keep. A tropical plant in a delivery truck during a Texas cold snap is a genuine risk, and heat packs only do so much. If you are in Boerne, Fair Oaks Ranch, Bulverde, Comfort, Kerrville, Helotes or San Antonio, collecting in person removes that variable entirely — the plant goes from our greenhouse into your warm car and into your house.
For anyone further afield, we pack with heat packs from now until spring and time shipments to avoid a plant sitting in a depot over a weekend.
See what is rooted and ready, or request something specific — autumn requests give us the whole winter to grow them on properly for spring.