- Compost disease-free annuals and vegetable crops that have finished producing.
- Cultivate and add compost to the soil for fall and winter vegetables and annuals.
- Dig, divide, and replant overgrown perennials as they finish blooming.
- Weed and amend beds before replanting.
- If not purchased pre-chilled, put tuilip, narcissus, and hyacinth bulbs in the refrigerator for 6 weeks prior to planting.
- Sow native bunch grass seed on bare slopes to prevent erosion.
- Mulch cane berries.
- Consider extending vegetable season with floating row cover, mulch, or plastic domes. (Gallon milk containers with the bottom removed work well.)
- Attend the Master Gardener Fall Plant Sale on September 24.
- Grapes, use organic mulch or P only, not N
- Mature fruit trees
- Cool season turfgrass with N
- Young conifers, but not those over two years old
- Table grapes for powdery mildew
What to Plant in September
- Sow seeds for columbine, lupine, California poppy.
- Divide and replant perennials.
- Transplant cool-weather annuals such as violas, pansies, fairy primroses, calendulas, cyclamen, stock, and snapdragons.
- Divide and replant bulbs and rhizomes.
- Transplant cabbage, broccoli, cauliflower, and kale.
- Direct seed beets, bok choy, spinach, lettuce, peas, radishes, carrots, chard, parsley, and cilantro.
- This is the ideal time to sow a new lawn or reseed bare spots.
- Think about reducing the size of your lawn to conserve resources.
- Seed for erosion control on slopes.
- Plant clover or fava beans to improve soil structure in your vegetable garden.