Seeds To Order in September for Winter Harvests, Earlier Flowers, and a Beautiful Start to your 2027 Garden

September is the clever gardener’s shopping month: order hardy annuals for fall sowing, cold-stratification candidates for winter, and reliable vegetables for an earlier spring harvest, choosing varieties that suit your USDA zone before the best stock disappears.

In my experience, a modest September order is far more useful than a panicked February splurge. You have time to read the packets, make a sensible plan, and label everything before the back yard becomes a springtime courtroom in which every seedling claims it was meant to go somewhere else.

Some seeds want autumn’s cool embrace, while others simply deserve a place at the front of the line; it is the useful planning companion to what to plant in September, and a seed storage organizer from Amazon will spare you several botanical mysteries next year.

Hardy Annuals For Spring

My first September order always includes hardy annuals. They are the garden’s early risers: given a chance to establish roots in fall, they often make larger plants and flower weeks ahead of their spring-sown cousins.

Calendula (Calendula officinalis) is the obvious charmer. Choose rich orange varieties for cutting, pale apricots for a quieter border, or a mix if you are constitutionally incapable of choosing. In Zones 7–10, sow it directly where it is to flower in a sunny, well-drained bed. In cooler zones, order now and sow under cover in late winter. The flowers are cheerful enough to make even a muddy March feel like a personal affront to winter.

Also put sweet pea (Lathyrus odoratus) on the list, particularly if you garden in the temperate Zones 3–8 where cool springs suit it best. Fall-sown sweet peas need protection from severe cold, but their root systems are better for the head start. I sow mine in deep modules, then spend the winter congratulating myself whenever I remember to water them. Our guide on how to grow sweet peas from seed explains the essentials.

Order larkspur (Consolida ajacis) too, if you like a cutting garden with a bit of old-world theatre. It dislikes root disturbance, so direct sow in fall where winters are not excessively wet; gardeners in colder or soggier areas can wait until the soil is workable in spring. A Giant Imperial larkspur mix from True Leaf Market brings those wonderfully spired blues, pinks, and whites to the party.

Seeds That Need Winter

Certain perennials have evolved to distrust a warm spell. Their seed will not wake until it has experienced a period of cold and moisture, known as cold stratification. Rather like many gardeners, they need a good winter before they are ready to face the world.

Coneflower (Echinacea purpurea) is a strong candidate. In Zones 3–8, sow seed outdoors in a prepared patch from late September onward, covering it only lightly. Winter does the tedious work, and seedlings emerge when conditions are right.

The payoff is a long-lived perennial with generous daisy flowers and an open invitation to pollinators. For more options, see our selection of flowers you can sow in September.

Butterfly weed (Asclepias tuberosa) and other milkweeds deserve a place in warm, sunny borders, especially in temperate Zones 3–9. They need cold treatment, too, and fall sowing is the least fussy route. Scatter the seed in its final position, mark the spot well, and resist the urge to “tidy” it away in April. I have done this. It is one of gardening’s more expensive forms of optimism.

If your winter is mild, or your ground is permanently saturated, use a refrigerator instead: place seed in a labeled bag with barely damp vermiculite or paper towel for the period specified on the packet. A small bag of vermiculite from Ace Hardware is useful for this and for seed-starting mixes.

Natural winter exposure is simpler, but labels are non-negotiable; all stratifying seeds look remarkably alike once they have been placed in the fridge beside the mustard.

Vegetables Worth Ordering Before Winter

September is also the moment to secure vegetable varieties bred for cool weather. The distinction matters. A packet may say “lettuce,” but a delicate summer variety will regard a frosty night with the emotional fortitude of a houseplant on vacation.

Order corn salad (Valerianella locusta), arugula (Eruca vesicaria), and winter lettuce (Lactuca sativa) for immediate sowing. In Zones 6–9, these can provide fall and winter pickings with a cloche, cold frame, or row cover. In Zones 3–5, sow them in a greenhouse, hoop house, or other protected setup. Succession sowing is the secret; one heroic row of arugula is not a salad program, merely a garnish with ambition.

Fava bean (Vicia faba) is another excellent September purchase. Look for hardy fall varieties such as ‘Aquadulce’, which can establish before winter and race away in spring. In colder zones, wait until early spring, or grow them beneath protection if your soil freezes hard.

They dislike waterlogging more than cold, so avoid a low patch where rain gathers with the determination of a family reunion. Our guide to vegetables to plant in fall has more useful timing advice.

I also order cilantro (Coriandrum sativum) every September. In Zones 7–10 it can be direct sown in stages for tender fall leaves; in cooler regions, sow it in pots near a bright window or greenhouse.

Buy more than you think you need. Cilantro has an extraordinary ability to bolt, vanish, or be harvested by everyone in the household except the person who sowed it.

Buy For Your Zone, Not The Catalog Cover

Seed catalogs are glorious, but they are also dangerously persuasive. A flower photographed in a Tuscan haze may be entirely wrong for a Minnesota spring, while a variety that appears rather plain in a packet can be a superstar in your particular climate.

Gardeners in Zones 3–5 should prioritize hardy annuals, cold-stratification perennials, and seeds for protected late-winter sowing. Choose varieties with shorter days to maturity and hold tender crops until spring.

In Zones 6–7, fall sowing opens up significantly, though a cold frame is still a handsome insurance policy. Gardeners in Zones 8–10 can sow a wide range of cool-season edibles and annual flowers now, while avoiding varieties that need prolonged hard freezes to germinate.

Your first fall task is to check your frost dates, then match the packet’s timing to your real conditions rather than the date on the calendar. This is especially important for winter vegetables to plant in September, where a difference of two weeks can mean salad rather than sadness.

Keep The Collection Useful, Not Chaotic

Before ordering, take five minutes to audit what you have. Seed remains viable for different lengths of time, but storage matters enormously: cool, dark, and dry beats a steamy garage shelf every time. I keep open packets in labeled envelopes inside a lidded box, grouped by flowers, vegetables, and 'entirely irresistible but not yet assigned a bed'.

Buy only enough to cover your likely sowing plan, plus a little for succession or the inevitable slug-related negotiations. If you are starting a sizable crop, these reusable seedling trays from Amazon are more practical than an elaborate collection of yogurt pots, however virtuous the latter may feel.

September Is for Seed Catalogs

September is not the end of the gardening year. It is the moment when the sensible gardener, preferably with a cup of something restorative, quietly gets ahead. Soil still holds summer warmth, nights are cooler, and the mail-order seed world has not yet been picked over by the January crowd who suddenly decide they need 18 varieties of tomato.

The key is not to order every beautiful packet that catches your eye. That way lies a drawer full of optimism and, eventually, seed packets with the melancholy air of forgotten theater tickets. Instead, buy for a purpose: seeds to sow now, seeds that need winter’s cold to germinate, and seeds you will want ready for late-winter sowing.

If you are unsure what can go directly into beds now, our guide to flowers to sow in September is a helpful place to begin. In warm temperate regions, roughly USDA Zones 7–9, fall sowing can be wonderfully productive. In Zones 3–6, concentrate on protected sowings and species that benefit from natural winter chilling.

What to Shop

The real pleasure of seeds to order in September is not merely beating the spring rush. It is the delicious knowledge that, while the garden appears to be winding down, next year has already begun, quietly, in a handful of packets, waiting for its cue.

If you love inspiring garden ideas, outdoor advice, and the latest news, why not sign up for our newsletter and get the latest features delivered straight to your inbox?