Gardener’s To-Do List for September

If you don’t know what USDA Plant Hardiness Zone you live in, check the map here to find out.

To-Do List for Zone 3

• Plant new fall bulbs so they develop roots before the ground freezes.
• Harvest corn, potatoes, apples, cucumbers, tomatoes, squash, and strawberries before a killing frost.
• If tomato vines are covered with green fruit, pull up whole plants and hang them in a basement or garage until fruits ripen.
• After onion tops have fallen over, dig the bulbs and let them cure on the soil surface for about a week before you store them.
• After harvesting, spread compost over the soil surface.
• Rake leaves and clean up plant debris, then add them to the compost pile.

To-Do List for Zone 4

• On the first of the month, plant spinach for overwintering.
• Use up any remaining compost in your bins to make room for the leaves you’ll soon add.
• Dig up and store tender bulbs and tubers, such as cannas and dahlias.
• Pick the seedpods and heads of any open-pollinated flowers you want to grow again next year; store the seeds in a cool, dry spot.
• Set out pansies, mums, and kale for later fall color.
• Plant bulbs and garlic in midmonth.
• Get ready to protect tender plants from early frost with row covers and blankets.
• Look for dry pods on bean plants; save the seed for planting next season.

To-Do List for Zone 5

• Sow seed of next year's biennial flowers, such as forget-me-nots (Myosotis sylvatica), sweet William (Dianthus barbatus), and foxglove.
• Plant spring-flowering bulbs.
• Dig up tender dahlias, cannas, caladium, and gladiolus before frost hits; store tubers and bulbs in a cool, dry spot.
• Start spinach and kale under row covers or in a coldframe for tasty winter salads.
• Still time to patch bare spots in the lawn—cover grass seed lightly with compost.
• Plant perennials to take advantage of cool weather and rainfall.

To-Do List for Zone 6

• Get fall compost cooking with the last of your grass clippings, spent plants, and leaves.
• As garden beds empty, sow quick-growing cover crops like winter rye.
• Sow spinach midmonth for spring harvest.
• Work spring-flowering bulbs into perennial beds.
• Plant garlic by month's end for harvest next June.
• Dig up, divide, and replant clumps of overgrown perennials.

To-Do List for Zone 7

• Early this month, sow seeds of mixed greens for fall and winter salads.
• Harvest young lettuce planted in August.
• Snip off long stems of parsley and freeze them in a bag or jar for winter use.
• Trim evergreen hedges (such as holly and privet) on the first cool day.
• Set out pansies in a spot that will receive full sun all winter.
• Harvest peanuts as soon as shells become hard.

To-Do List for Zone 8

• Plant transplants of broccoli, cauliflower, cabbage, and kale; surround them with a thick mulch to cool the soil.
• Direct-seed spinach, lettuce, beets, carrots, parsley, turnips, and kohlrabi.
• Plant pansies, stock (Matthiola incana), snapdragons, sweet alyssum (Lobularia maritima), Johnny-jump-ups (Viola tricolor), and pinks (Dianthus spp.).
• Apply a 1⁄2-inch layer of compost to areas of the lawn that are susceptible to brown patch; apply organic fertilizer to the entire lawn at the end of the month.

To-Do List for Zone 9

• Plant winter lettuce, peas, carrots, cole crops, and Asian greens.
• Harvest winter squash and pumpkins before frost, when their skin is hard enough to resist pressure from your thumbnail.
• Set out transplants of calendula, primroses, larkspur (Consolida ambigua), snapdragons, bachelor's buttons (Centaurea cyanus), stock (Matthiola incana), and pansies.
• Refrigerate spring bulbs for 6 weeks to plant later this fall.
• Pick ‘Bartlett' pears for ripening indoors, but allow Asian pears and ‘Seckel' pears to ripen on the tree.
• Protect grapes from birds and wasps by covering the ripening clusters with brown paper lunch bags.

To-Do List for Zone 10

• Prune poinsettias for holiday bloom.
• As grasshopper numbers die down, plant tuberoses (Polianthes tuberosa), gloriosa lilies, amaryllis, and other subtropical bulbs and rhizomes.
• Plant okra. It’s your last chance of the season.
• Seed cucurbits and herbs, and set out transplants of tomatoes, peppers, and onions.
• Repair or replace drip irrigation lines.
• Work in soil amendments, including compost, bonemeal, and greensand.
   

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