January in the Desert Garden

January is the coldest month in the low desert — a quiet, dormant stretch that’s perfect for pruning deciduous trees and roses, planting bare-root stock, and guarding tender plants against frost.

What To Do in January

Grass

• Winter ryegrass is actively growing — mow at 1½ to 2 inches and water about once a week, a little more during a warm, dry stretch.
• Hold off fertilizing dormant Bermuda; feed the rye lightly if it looks pale.
• Keep foot traffic off the lawn on frosty mornings — walking on frozen blades bruises them.

Trees & Shrubs

• This is the month for dormant pruning of deciduous trees and shrubs, while they’re leafless and you can read the structure.
• Plant bare-root roses, fruit trees, grapes, and shade trees now, while they’re dormant and inexpensive.
• Do not prune frost-tender plants such as bougainvillea, lantana, oleander, and citrus yet — that ragged-looking growth is insulating the plant. Wait until after the last frost.
• Harvest citrus as it ripens. A light frost actually sweetens oranges and grapefruit.

Flowers

• Keep planting cool-season color: pansies, violas, snapdragons, petunias, dianthus, and stock.
• Deadhead spent blooms to keep annuals producing.
• Bare-root and dormant perennials can go in the ground now.

Vegetables

• Keep planting and harvesting cool-season crops: lettuce, spinach, kale, chard, broccoli, cauliflower, cabbage, carrots, beets, radishes, peas, and onions.
• Plant asparagus crowns and bare-root artichokes.
• Harvest leaf lettuce a few outer leaves at a time and the plant will keep producing.

Don’t Make These Garden Mistakes in January

1. Don’t prune frost-tender plants — wait until mid-February or later, once the frost danger has passed.
2. Don’t forget to cover tender plants on frost nights, and uncover them during the day so they can breathe and take in sun.
3. Don’t overwater. Cool weather and dormant roots mean plants need far less water than in summer.
4. Don’t skip the dormant-season cleanup — raking out leaf litter now removes overwintering pests and disease.
5. Don’t fertilize dormant plants; you’ll push tender new growth right before a frost.