October is the real start of “cool season” gardening here—perfect for planting, refreshing beds, and enjoying the shift to softer weather:

Planting

  • Cool-Season Vegetables: Sow seeds or transplants of lettuce, kale, spinach, arugula, broccoli, cauliflower, peas, carrots, beets, radishes, and Swiss chard.
  • Herbs: Plant parsley, cilantro, dill, chives, and fennel.
  • Flowers (Cool-Season Color): Add pansies, violas, snapdragons, calendula, dianthus, Iceland poppies, and stock for vibrant winter beds.
  • Trees & Shrubs: October is one of the best months to plant trees, shrubs, and hedges—cooler temps mean less stress and better root growth.

Maintenance

  • Refresh Mulch: Top up mulch around beds to conserve soil moisture and suppress weeds.
  • Clean Up Beds: Remove summer annuals and spent vegetable plants.
  • Pruning: Lightly shape shrubs and hedges. Wait on heavy pruning of roses and fruit trees until winter dormancy.
  • Weeding: Stay on top of weeds before cooler-season rains help them spread.

Watering

  • Adjust Irrigation: Cooler days and shorter daylight mean plants need less water. Cut back but don’t stop entirely.
  • Deep Water New Plantings: Ensure newly planted trees, shrubs, and perennials are well-watered until established.

Seasonal Highlights

  • Fall Foliage: Plant or enjoy deciduous trees like liquidambar (sweetgum), Chinese pistache, and ginkgo for brilliant autumn color.
  • Bulbs: Chill spring-blooming bulbs like tulips and hyacinths for planting in late November or December. Daffodils, freesia, and ranunculus can go directly in now.

Garden Health

  • Pest Watch: Keep an eye out for aphids, whiteflies, and caterpillars on tender new growth. Treat early with insecticidal soap if needed.
  • Fertilize: Use a balanced organic fertilizer for vegetables and flowers to encourage strong growth. Feed citrus and fruit trees lightly if needed.

October is all about starting fresh in Zone 10b—cool-season veggies, vibrant winter flowers, and fall color give gardens new life after the heat of summer.