I DARE YOU: DO A SURVEY of your garden, right this minute. Go outside with a clipboard, and make a headcount of what’s still queued up and waiting to show off (compared to what’s spent and done for the year).  Then commit to lengthening the still-to-go list with some well-planned September planting. That’s how this year’s September garden chores begin: with analysis, so you can do enhancements–and yes, I know: we also have harvests to process, weeds to outsmart, lawns to renovate, and more. But let’s not skip this primetime strategic opportunity to not just analyze, but also act to improve the year-round view out the window by planting and transplanting this month.

Here in Zone 5B, where frost can come in late September or early October, you’d think I’d be feeling more fatalistic—that the season’s “end” was in sight.

Instead I have gradually loaded my garden with things that flower or fruit or form great seedpods late, or take on fall foliage colors, or with good offseason structure or bark.  On the other end of the calendar, I’ve worked hard to layer in extra-early performers. In my region that means things that start up in March, as snow melts–such as minor bulbs or early perennials like hellebores. A 365-day garden, remember?

Topic by topic, now, the rest of the September garden chores:

weed and pest control and prevention

WEED WAR! Now is the time to minimize weed woes for next year. Some weeds are actually easier to thwart in late summer and fall, like these.

THE WAY WE MOW—in fall, and throughout the lawn’s active growing season—and when we do our raking up of debris can really affect how many lawn weeds we have, particularly opportunists like crabgrass. Repair compaction, minimize weeds and overseed now.

SPECIFIC WEED WISDOM:

• Clearweed, or Pilea pumila 
• A weed I planted (oops!), Houttuynia or chameleon plant
• Garlic mustard, Alliaria petiolata
• Commelina and Galinsoga, two more opponents I tangle with
• How to ID your weeds—links to online guides
• Smothering weeds with cardboard and newspaper
• Piling on the mulch for weed suppression and control

PEST PROBLEMS? When you start your fall cleanup, do so with pest control in mind, too. Deer, voles, cabbage worms, squash bugs and other garden pests can be limited with tactics like this.

vegetable garden

SAVE SEED: The time is now for saving tomato seed (and other “wet” seeds such as peppers, squash, cucumber, melon). How to save tomato seed.

SEND IN SOIL SAMPLES for testing if you’re seeing poor results in some beds. Contact your local cooperative extension on how to sample.

MY FALL VEGETABLE GARDEN PLANS were covered in this archive story and podcast. Still ahead to plant here: more salad, garlic (next month) and spinach. How you can plan for an extended harvest in every region.

KEEP ASPARAGUS well weeded and watered, too. Let asparagus ferns grow till hard frost, when they are fully browned—or even leave them up till spring cleanup.

GARLIC should be curing in an airy, sheltered place. Read all about growing garlic, and storing your harvest–and order bulbs now for October-ish planting.

TOMATO, CUKE OR SQUASH TROUBLES? Tomatoes have a range of possible problems, but who could go without them? If your issue is cucumbers or summer squash, start here. Peppers can be tricky in some seasons; pepper tips and recipes and storage tips.

AS AREAS COME EMPTY from harvest, build vegetable-garden soil by sowing cover crops. These “green manures” will be turned under to improve soil tilth and fertility. Don’t sow in areas reserved for fall-planted garlic, or very early spring crops.

I FREEZE MANY HERBS, including parsley, rosemary and chives, or make them into pestos to freeze as well. Here’s how.  If it’s vegetables you are storing, start here. Lots more harvest-stashing recipe ideas, from pickles to frozen peaches.

flower garden

DON’T DEADHEAD FADED perennials, biennials and annuals if you want to collect seed (non-hybrids only) or let some self-sow. Nicotiana, annual poppies, larkspur, clary sage and many others fall into this leave-alone group. So do plants with showy or bird-friendly seedheads, like coneflowers, some sedums, clematis and grasses.

DAYLILIES can be dug and divided as they complete bloom, right into fall, if needed.

PEONIES are best divided and transplanted in late August through September, if they need it. Remember with these fussy guys that “eyes” must not be buried more than an inch or two beneath the soil surface.

MANY POPULAR ANNUALS can be overwintered as rooted cuttings rather than nursing along leggy older specimens. Geraniums, coleus, wax begonias, even impatiens (to name just a few common ones), if grown in good light indoors and kept pinched and bushy, will yield another generation of cuttings for next spring’s transplants. Expend this effort and space on an unusual form of something, not the garden variety.

DID YOU HAVE IMPATIENS problems? Learn about downy mildew and plan to avoid it next year.

IF TUBEROUS BEGONIAS like ‘Bonfire’ or ‘Bellfire’ are starting to go slack, let them dry off and rest early, or they will rot. Take your cue from the plants!

ORDER BULBS promptly, and plant as they arrive (lilies most urgently). Top 7 tips on shopping smart for flower bulbs.  Many bulb-growing questions are answered in my Bulb FAQ.

PREPARE NEW beds for fall planting by smothering grass or weeds with layers of recycled corrugated cardboard or thick layers of newspaper, then put mulch on top.

RE-EDGE BEDS to make a clean line and define them. Don’t let them get overrun just because summer’s wound down. A clean edge makes a big difference.

trees and shrubs

IF YOU’RE ON THE DRY SIDE, be sure to water trees and shrubs through hard frost, so that they enter dormancy well-hydrated. Evergreens (needled ones and broadleaf types like rhododendron, too) are particularly vulnerable to desiccation and winterburn otherwise.

DON’T PANIC IF EVERGREENS start to show some browning or yellowing of needles this month and next. The oldest, innermost needles typically shed after a few years.

ALWAYS BE on the lookout for dead, damaged, diseased wood in trees and shrubs and prune them out as discovered. Ditto with suckers and water sprouts. No hard pruning now, though; too late to risk encouraging regrowth. No fertilizer this late in the season, either.

houseplants

REST AMARYLLIS BULBS by putting them in a dry, dark place where they will have no water at all for a couple of months. I put mine in a little-used closet.

IF HOUSEPLANTS NEED repotting, do it before they come inside later this month (less messy than in the house!). Don’t step up more than an inch (on small pots) or a couple (on large ones). Most plants don’t like to swim in their containers.

lawns

MID-AUGUST TO MID-SEPTEMBER is prime lawn-renovation and planting time in the North. Have you reseeded yet? Paul Tukey at SafeLawns [dot] org shares some overseeding how-to’s.

DON’T BAG OR RAKE clippings; let them lie on the lawn to return Nitrogen to the soil, right through the last mowing in late autumn. An exception: If you have crabgrass, and it’s setting seed.

compost heap and mulch

I USE BULK MULCH, which is cheaper than the packaged kind and also eliminates the waste of all those heavyweight plastic bags. Many local nurseries deliver. Top up mulch in all garden beds as they get cleaned up gradually. What good mulch is made of.

DON’T LET THE HEAP dry out completely, or it will not “cook.” Turning it to aerate will also hasten decomposition, but things will rot eventually even if not turned. I extract more finished material and screen it each fall, to work into the gardens (and make more room for incoming fresh debris).

(On using this list in your garden: The monthly A Way to Garden chores are based on my Zone 5B Berkshire MA/Hudson Valley NY location; adjust accordingly.)