I look at cleaning up the garden in stages, not as a one and done situation! There are many ways to answer the question, “when should I start my fall garden cleanup”, let’s look at what really works. My fall clean up also keeps pollinators in mind.
As always, Nature is in charge. Sometimes weather patterns shift wildly and your first frost dates are weeks earlier or later than last year. Nature loves to keep us guessing.
So, since dates don’t really work for me, but phases of what comes in first, second and third has proved more helpful for me – I’ve gathered my best practices here.
I hope it helps you tackle the end of the season vegetable garden clean up as well.
Protect Your Potted Plants
Usually, if you’re starting to wonder about what should come in, you should stop what you’re doing and head to the garden to Bring in Any Tender Potted Plants right away. I have a Lemon Tree, Bay Laurel and some larger Rosemary plants all in pots, so they come in once the temps start dropping to 50°F.
Fall is also a great time to build a Hügelkultur or No Dig garden bed!
*As you clean up consider planting a cover crop if you have 4-6 weeks before your expected first frost.
*All the fall prep that I do considers No Dig Garden Clean Up practices.
Phase 1: Harvest + Remove
(Long Before the First Frost)
Temperature Guide: Consistent nighttime lows around 40°F.
Cut these crops at the soil level completely or harvest all remaining fruit immediately. They have zero frost tolerance and will show damage to plant and fruit/veg overnight if exposed to anything below 35°F
Tender Herbs:
I usually do a major last harvest of herbs like Basil, Thai Basil, Lemongrass and Marjoram before the temps drop to below 40°F
Tender Veggies:
Tomatoes, peppers, eggplants, cucumbers, green beans, and summer squash/zucchini. Tip: Pull green tomatoes and let them ripen indoors on your counter. Or make Fermented Green Tomato Salsa…
Vines & Melons:
Pumpkins, watermelons, summer and winter squash. A light frost will kill the vine, but not usually harm the squash- however, you’re probably not going to get much more growth out of them with lower light levels. Cut with a few inches of stem left. Remember to cure winter squash indoors in a sunny, warm (80 degrees Fahrenheit), well-ventilated space for long-term storage
Invasive/Diseased Debris:
Pull any weeds that have gone to seed so they don’t sprout next spring. If any tomato or vine crops suffered from blight or powdery mildew, burn or bag them up and discard them. Do not compost diseased plants in home compost bins unless you really keep your compost cooking (over 140°F for 3 days) which is hard to do as winter temperatures are setting in here.
Phase 2: Leave & Protect
(During Hard Frost/ Light Freeze)
Temperature Guide: Nighttime lows dipping to 28°F to 32°F.
Many cool-season vegetables actually taste better after a light frost. The cold triggers a defense mechanism where starches convert into sugars, acting as natural antifreeze and leaving your cold hardy plants sweeter for the experience.
What to Leave Without Protection:
Kale, Swiss chard, collard greens, leeks, Brussels sprouts, cabbage, and broccoli. Kale can easily survive down to 20°F without protection.
Root Vegetables:
Carrots, beets, parsnips, rutabagas, and turnips can be kept in the ground; they will hold beautifully as long as the soil itself isn’t frozen.
How to Protect:
If you want to keep harvesting salad greens (spinach, lettuce, arugula), cover them with a floating row cover, or pop up low tunnels on nights when temperatures drop below 32°F. Full how to information in my article Season Extension: Garden + Harvest into Winter.
Phase 3: Final Dig & Soil Prep
(Before the Ground Freezes)
Temperature Guide: Before a Hard Freeze (below 25°F) solidifies the soil.
Dig or Insulate:
Harvest all remaining root vegetables (carrots, parsnips) unless you want to try to overwinter them. I have successfully done this by adding around a foot of dry straw over carrots, then adding some garden plastic (same as I use for low tunnels) over that and securing it in- this way I get amazingly sweet and crunchy carrots just as the ground thaws in spring, usually March in my area. If left to freeze in the ground without additional insulation they will become impossible to dig out and will rot during the spring thaw.
Plant Next Year’s Garlic:
Mid- to late-October is the perfect window to plant your hardneck garlic cloves in Minnesota. Read more in my full article on Growing Great Garlic.
Place next Spring’s Structures:
If you plan to get a jump start on planting next spring, place your hoops this fall. Being able to pound in stakes and maybe even place the PVC hoops for next year’s low tunnels now will get you a step ahead. I do not recommend putting plastic up over the PVC as our winter usually has lots of snow, melting, ice etc. that will destroy the plastic and hoops.
Feed and Tuck In the Soil:
Try not to leave Zone 4 soil bare over winter—the harsh winter winds and snowmelt cause major erosion and nutrient loss. You have a few options here. Spread a 2- to 3-inch layer of compost over your cleaned beds. Or, top it with a thick blanket of shredded leaves or clean straw mulch. Or, if you have 4-6 weeks before freezing plant a cover crop to keep living roots in the ground, feeding the soil life longer into the winter.
Hoses & Irrigation:
Disconnect, drain, and roll up all garden hoses. Turn off the outdoor water valve and drain the spigots to prevent burst pipes.
Containers:
Empty ceramic, terra-cotta, and fabric pots. You can toss extra soil on top of garden beds that didn’t get a layer of compost, mulch or cover crops too. Freezing soil expands and will likely crack rigid pots. Store them upside down in a garage or shed.
FAQ’s For Fall Garden Cleanup
Q: When should I start my fall garden cleanup?
A: Depend on what you’re growing and how frost tolerant the plants are. I have a great guide for low temps plants can handle on Pinterest.
Q: What is typically included in a fall clean up?
A: Everything from cutting away dead annuals, raking leaves (but keep on site to give overwintering insects habitat) to adding compost and mulch to increase soil health.
Q: What plants should not be cut down in the fall?
A: Perennials do not need to be cut down in the fall, annuals should be. Even though we used to clean up a lot more perennials in the fall, now we know that many of our pollinator friends use the stems of perennials to overwinter in.
Taking these steps in the right order will help you tackle jobs as needed, and set you up for a great start to next Spring in the garden.
Plus you’ll be able to enjoy those latest of fall harvests – maybe even into winter!
Peas, Michelle
I'd love to hear your thoughts!