Coastal and Tropical South
Know When to Repot
For some, repotting is an annual ritual, but to others it is a real stumper to figure out when, how, or even why to do it. Repot container plants anytime the pot gets so top-heavy that it tips over between irrigations, when you can see roots in the drain hole, or if water pours through indicating root crowding. If none of that happens, it is still a wise idea to repot young specimens once a year so there is ample room for root growth. Prepare a well-drained potting mix and choose a container that is one inch bigger all around. Gently slip the root ball out of the pot, and if needed, press on or break the pot to avoid damaging the roots. Loosen or cut tightly bound roots before repotting. Water newly repotted plants carefully while roots are regenerating to avoid overwatering.
Choose Bulbs for Fall Planting
The selection of many favorite bulbing plants is best in autumn. Even so, check each bulb or package for soft spots and downright crunchy texture. Both indicate the bulbs have been damaged and are unlikely to grow. Traditionally, the most popular are daffodils and hyacinths, but with the exceptions of caladiums, many others that do well in our gardens can be planted in fall. Check out the entire onion family, including the edibles, which can be grown from seed and sets now, and regal flowering allium, the biggest purple flower in the spring garden. Red spiders and other lycoris, pink hurricane lilies, huge amaryllis, and cultivated varieties of swamp white spider lilies are among the jewels you should be seeking now.
Redo Beds and Containers for Continued Color
September is the time to spruce up the big containers and beds of annual flowers. You may choose to cut back leggy plants, or pull up and compost them, replanting from seed and small transplants. Annuals such as pansies, violas, petunias, and snapdragons are widely available as transplants for now, which is good since their small seeds can be difficult to start. Calendula, bachelor's button, and candytuft, however, come easily from seed sown directly in the garden.
Some perennial plants can go for years without being divided, while others stop blooming as soon as they get crowded. The best example of perennials that need to be divided and replanted annually for best flowering may be daisies. Clumps of Shasta daisies do not bloom well if left undivided for even two years or if weeds like bermuda grass are allowed to take over the bed. Dig up entire clumps and groom to remove weeds, yellowed leaves, and old flower heads. Part the leaves and cut straight through the crown and roots to form a division about two inches square.
Plan to Protect Plants
No matter where you live, some plants deserve protection from winter winds and rain, even if the temperature is not an issue. Winter flowering vines such as tropical pandanus can grow fully exposed in the Tropics zone, but relentless wind or salt spray can limit the flower display. Even there, a pergola or courtyard wall can protect the developing flowers. This desire to shelter our plants may explain our great fondness for screen porches, greenhouses, and coldframes of all sorts, not to mention the indoor garden. If the greenhouse needs reglazing, get busy now so it will be ready when you need it. Take steps to have other safe sites ready by setting up benches, replacing plastic covers, adding supplemental light where needed, and locating those all important plant saucers and dollies.