Prune Back Diseased Plants
If your hollyhocks or snapdragons have developed rust disease, now is the time to cut them back. Place the stems and foliage in the garbage (rather than the compost pile) so you don't risk contaminating the beds with overwintered disease spores.
Divide and Transplant Iris
Iris won't bloom well if they are overcrowded. There's still time to dig and divide the plants before winter weather sets in. Discard the old, spent center sections; keep the young, vigorous rhizomes for transplanting. Plant the rhizomes just beneath the soil surface and water in well. To help plants get established, add some compost and/or an all-purpose, 5-10-5 fertilizer when replanting.
Add Color to the Fall Landscape
Early fall is when garden centers offer real values on autumn-blooming mums and pansies. Fall perennials thrive with the cool weather and continue to put on an attractive show into the month of December. Work compost into the soil when planting to improve drainage and enhance winter survival rates.
Take Geranium Cuttings
You can take cuttings from your favorite geraniums to grow indoors over the winter months. Cut a blooming stem at least seven leaves back, wash it thoroughly, and snap off the blossom and the bottom two leaves, leaving 5 leaves. Dip the bottom in rooting hormone and gently plant in moist potting soil. Keep away from direct sun until you see new growth.
Stop Cutting Roses
To encourage your roses to harden off for the winter, stop harvesting flowers by the end of September. Cut what you need for bouquets, dried blooms, and potpourri, and don't cut any more. Let the flowers wither, and gently pull the petals off with your hands for drying. Allow the hips to develop. They will help send a message to the plants to harden off.