October Checklist
WHAT TO PLANT
ARIZONA’S LOW DESERT
Cool-season vegetables—Plant peas, chard, carrots, daikon, endive, lettuce, spinach, cabbage, beets, radish, mustard, turnips and kale from seed now. Protect new plantings with floating row covers to prevent birds or other pests from eating young plants. Transplant broccoli, Brussels sprouts and cauliflower starts as soon as possible so they can develop before spring’s warm weather comes. Keep an eye out at your local nursery for ‘Graffiti,’ a stunning deep purple variety of cauliflower.
Herbs—Plant cilantro, dill, parsley, thyme, chives and chamomile from seeds. Oregano, mint and thyme will become

established more quickly if transplanted now. Transplant catnip now to treat your feline friends through next spring. Bay trees (Laurus nobilis) will provide a lifetime of bay leaves in your low-desert garden. Plant bay this month, allowing room for at least 20 feet to spread, and be sure to protect from frost this winter.
Wildflowers—Sow seeds of wildflowers into loosened soil and water every week or two until they germinate in the spring. African daisy (Osteospermum spp.) is a common addition to Southwest wildflower mixes. Be aware that they can become weedy and spread into areas they aren’t welcome, such as desert preserves. Avoid seed mixes that contain African daisies if you live adjacent to natural desert areas, such as mountain preserves or national parks.
Cool-season flowers—Fill hanging baskets with sweet alyssum, sweet pea and petunias. Consider edible alternatives, such as calendula and violets.
Bulbs—When planning your bulb garden, plant taller varieties, such as amaryllis (pictured right), in the background and shorter types, such as grape hyacinth, in the front.
Trees, shrubs and vines—The warm days and cool nights of October are perfect for establishing new plantings of desert-adapted landscape plants. For a bee-friendly garden, consider the native desert shrub bee brush (Aloysia gratissima) (pictured above), which produces fragrant white flowers during the warmer months.
Cacti and succulents—For a genuinely low-maintenance landscape, plant agaves, aloes, euphorbias and cacti now.

ARIZONA’S MIDDLE ELEVATIONS
Cool-season vegetables—Plant onion sets now. Be sure to select day-neutral varieties, as they have a better chance of forming bulbs early in the spring than do long-day varieties. If you are willing to guard against the frost, set out transplants of chard, spinach and kale now.
Cover crops—Build healthy soil for your spring vegetable garden by planting cool season cover crops. Barley, oats and rye are good for adding lots of organic matter and loosening hard soil. Use fava beans to add nitrogen. Remember to chop cover crops down and incorporate into the soil next spring, at least 30 days before planting your garden.
Cool-season flowers—Transplant colorful pansies, violets, snapdragon, stock and petunias into a sunny location.
ARIZONA’S HIGH COUNTRY
Native trees and shrubs—Plant evergreens, such as pines, junipers, spruce and cypress. For visual interest, choose species with different shades of foliage. ‘Gold Lace’ juniper (Juniperus chinensis ‘Gold Lace’) is a compact type with bright gold branch tips. Blue spruce (Picea pungens) is an Arizona native that can reach a height of 100 feet. Always check the mature size of any plant before giving it a permanent home in your landscape. Protect tender trunks from rabbits and deer by surrounding them with poultry wire.

Bay tree blossoms
GARDEN MAINTENANCE
ALL ELEVATIONS
Remove weeds—The 2017 monsoon season pushed a blanket of weeds up throughout the state. Pull them by hand, chop them up, and add them to the compost pile. If left in place, they can become a refuge for pests that harm landscape and garden plants.
ARIZONA’S LOW DESERTS
Finish pruning trees and shrubs—Remove any limbs damaged during summer storms now before cold weather settles in.
Thin vegetable seedlings—Check seed packets for optimal spacing, and thin recently emerged seedlings accordingly. Root vegetables, such as beets and carrots, will not develop properly if crowded.
Harvest pomegranates—Warm evening temperatures prevent pomegranates from turning the deep red we expect. The fruits may still be ripe even if the color hasn’t changed. Sample fruit every few days and begin harvest when the arils surrounding the seeds are juicy and sweet.
ARIZONA’S MIDDLE ELEVATIONS
Prepare for frost—Apply a thick layer of mulch to the soil surface to insulate the soil and inhibit weed growth.
Adjust irrigation—Cooler fall temperatures decrease plant water demand. Cut back on water without turning it off all together. Even dormant plants require periodic irrigation.
ARIZONA’S HIGH COUNTRY
Get ideas for next season—Visit public gardens to see mature plants in the landscape. The Flagstaff Arboretum offers free garden tours with paid admission through Oct. 31. For tour times and directions, visit https://www.thearb.org/visit/tours-and-activities/.
Kelly Young is an agroecology researcher and educator with a master’s degree in botany from ASU.