As the weather turns, growth starts to slow, and September's jobs are about easing your plants toward autumn.
Reposition
Bring outdoor plants back in before the first cold nights. Any plants that spent summer outside, especially Cacti & Succulents need to come indoors before temperatures drop, ideally with a gradual transition rather than a sudden move. You could start with leaving them outside during the warmest part of the day, and moving them inside overnight
Check for pests
Check for hitchhiking pests on anything coming back indoors. A quick leaf check now saves an infestation later.
Reduce the feed
Start reducing feeding as growth slows down; there's less need to fuel it.
Water less
Begin cutting back watering frequency, as the growth slows and the temperature falls, you can adjust your watering schedule too.