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As Colorado gardening season winds down, here’s what you need to do now to prepare for fall, winter and next spring

From deadheading to preserving the late-season harvest, there’s a lot of work yet to be done this season

DENVER, CO. -  JULY 18:  Denver Post's Susan Clotfelter on  Thursday July 18, 2013.    (Photo By Cyrus McCrimmon/The Denver Post)

Right now, your tomato plants might still be reaching for the sky — or already winding down with the shortening days.

If you’ve been planting since April, you might feel exhausted and ready to hang up your shovel — or are completely unwilling to stop yourself. Wouldn’t a new plum tree go great here? What if I divided that feather reed grass and put it all along the west side? How can I get more shade, more light, a fountain,  an asparagus bed … ? Yes, gardening is, in fact, addictive.

That’s because every year is different. Continuing to experiment, dig and make mistakes are what makes gardening exciting.

So here are 30 short challenges to pursue if you want to savor what’s left of the long days and set yourself up for success — or maybe just surprises — next spring. There are some to do indoors if the day is too hot to be outside or the full moon keeps you awake. There are some to speed through outdoors as the dusk is settling and the bees are heading home, or early in the morning. Finally, there are some essential tools and plants to chase down to fuel next year’s dreams. Most can be completed within 15 minutes.

It's that time of summer when your tomato plants are providing lots of fruit before shutting down. (Susan Clotfelter, Special to The Denver Post)
It’s that time of summer when your tomato plants are providing lots of fruit before shutting down. (Susan Clotfelter, Special to The Denver Post)

Indoors


Order or buy fall bulbs. Do this ASAP, before your local garden centers and the best mail-order houses are sold out. Try dwarf irises (also known as reticulatas) or crocuses for early blooms and daffodils for mid-spring (more reliable blooms than many tulips). Alliums come in so many sizes, colors and bloom times that you’ll have a hard time choosing, but you can’t go wrong. Or choose Siberian irises, about half the size of the traditional bearded irises and a bit more drought-tolerant than regular bearded iris. Remember to include some varieties that will make pollinators happy.

Take notes. What, specifically, did you grow this year, and where, and when? Was it from seed or transplants? For example, I planted Hakurai turnips, which are a sweet turnip tasting like a mild radish. But I got them in too late and didn’t give them enough room or sunlight. Remember, if you can, when you planted and where; if you love something but it didn’t do so well, try relocating it next year. (Personally, I need to plant fewer tomatoes.)

Make a list of garden tools you need to replace, repair, sharpen or upgrade. Maybe you need a new soaker hose or trellis or birdbath fountain.

Defrost and clear out your auxiliary freezer to make room for this summer’s harvest and find any science projects that might be lurking in there. (Depending on freezer size, this may take more time, as I discovered when my deep freeze recently died in valiant service.) And, hey, why not share your oldest relic in the comments below?

Purge your seed vault. Generally speaking, seeds last longer here in Colorado. But anything over five years old can be guiltlessly gotten rid of, and for best germination rates, don’t keep them more than a few years. Set aside any packets of quick fall crops you think you might want to plant.

Order mulch. Whether you choose pea gravel, cedar or recycled rubber tires, mulch is not just the secret to less watering. It also insulates plants from temperature extremes, keeping soil warmer longer.

Make an appointment for sprinkler-system maintenance, repair or upgrades. Or, if you have a DIY system, assess how your current method is working (or isn’t) and get your parts ordered. Consider a smarter, more efficient system.

Call a landscape company about any renovations you want to have done in 2023. Their schedules are often set for months into the future, especially once the pandemic made homes into workplaces. Consider three things: the size and complexity of your project; your own expertise and willingness to spend time on maintenance; and how much you can spend. Get references from neighbors and your local garden center. Finally, don’t waste your time with anyone who can’t or won’t answer all your questions or talk to you like you’re a grown-up with a brain.

If you have medium or large trees that haven’t been pruned recently, call a certified arborist to make an appointment. Most likely, they’ll want to wait until trees have dropped their leaves and are fully dormant to do any pruning or limb removal.

Haunt your county agricultural extension service’s website to a) stay up to date on insect pests and diseases; b) take advantage of free or low-cost classes; and  c) learn about any new plants before you buy. Some tree species, for example, might need more wind protection than others, be toxic to pests or be a “Goldilocks” choice for your yard. Ditto for Plant Select, which highlights trees, shrubs and flowering plants that do especially well in our unique soil and climate conditions.

Out in the world with your wallet


Order your fall bulbs (like this camas) now, before garden centers sell out. (Susan Clotfelter, Special to The Denver Post)
Order your fall bulbs (like this camas) now, before garden centers sell out. (Susan Clotfelter, Special to The Denver Post)

Replace what’s broken. Did that hose finally give out and develop an even more annoying leak? Did you break the tip of your trowel levering rusty old metal edging out of the yard? Take your list from your tool evaluation chore and go shopping. Thrift stores such as Habitat for Humanity ReStore and ARC sometimes have still-good tools that someone offloaded when they upgraded. Here’s looking at you, new-to-me weed whacker.

Watering equipment just isn’t optional for Colorado gardeners, even if you do have a sprinkler system, because our temperature salsa dances across the freezing mark on a daily basis. If you’re trying to be as water-thrifty as possible – big props to you if that’s true – you’ll still need to baby some plants a bit to get them established. Try what I call “thrifty girl’s drip” – two nested buckets, one with small holes drilled in the bottom. Fill the buckets with the leaky one on top; carry to your plant and lift the leaky one out.

Buy trees, shrubs, perennials. There are bargains to be had! In fall, the soil holds onto summer’s warmth. You’ll likely need to rehydrate and re-pot these purchases immediately to nurse them back to vigorousness, so get some good garden soil at the same time. Perennials and shrubs planted in September will have a head start next spring, and the following year will leap into abundance. The notable exception: Many conifers, especially dwarf conifers.

Swap starts and seeds with a friend! In addition to being free, these babies may not have been as neglected as some big-box-store survivors. And when you see these treasures bloom, you’ll remember that gardening is social as well as solitary.

Give in to some yard art. Winter is coming, and it’s mostly gray and brown. It’s a great time to scoop up some outdoor accessories in metal or stone. If you think yard art is an abomination, then look for plants that provide some winter color and interest. Try a red-twig dogwood or a towering ornamental grass. Or a bright-gold arborvitae. (Landscape snobs call them “everybodys” because everybody’s got them — but there’s a reason for that: They’re easy to keep happy.)

Deep. Root. Watering. If you’re planting a tree this fall, remember that drip irrigation is what they need most. So look for a watering spike, which goes into the soil near, but not on top of, their roots, or something like a TreeGator, which you fill up quickly with a hose and then move on to other chores.

Soaker hoses. I’ve been upgrading my failing foam soaker hoses to Melnor’s tough fabric ones, and I’ve tried both the 25- and 50-foot versions. Jury’s still out on durability, but they certainly are easier to handle, move and store.

Bulbs! While mail-order houses might have great selection, first check out your local, independent garden centers. Running one of these businesses is not for the faint of heart. It’s highly seasonal, and rising utility and equipment costs can hit them hard. Second choice would be online vendors that focus on the Intermountain West region.

Don’t forget to visit area public gardens like the Denver Botanic Gardens and smaller equivalents in your town. They often celebrate the end of summer with plant sales. And while you’re there, get a membership.

Deadheading roses keeps the blooms coming as the season wanes. Follow up deadheading with watering. (Susan Clotfelter, Special to The Denver Post)
Deadheading roses keeps the blooms coming as the season wanes. Follow up deadheading with watering. (Susan Clotfelter, Special to The Denver Post)

In the garden


Deadhead, deadhead, deadhead (unless we’re talking about a rose whose hips — that fruit pod that forms at the base of a former bloom — are decorative). You can deadhead one large rosebush or three smaller ones in 15 minutes. Deadheading keeps the blooms coming as the season wanes. Follow up deadheading with watering.

Fight the hoppers. If grasshoppers have been a plague at your house, check out EcoBran, a low-concentration insecticide that USDA studies show does not harm bees or birds. Can’t get it? Bookmark the page and set a calendar alert so you can get it early next year; it’s most effective when the grasshoppers are young. And if you have plantings that the young pests seem to thrive in, try to reduce those areas (they seem to regard my volunteer lemon balm as their nursery).

Trap or evict nuisance wasps. Yellow jackets are out for sugar this time of year, so if they’re trying to crash your outdoor Wine Down Wednesdays or popsicle parties, get a couple of traps and place them away from the gathering area. Note areas where other wasp nests can be seen. But if these fierce garden predators aren’t bothering you, just note their locations and let them be for now; grasshoppers are among their prey. And by all means, don’t harm the beneficial parasitic wasps and bee mimics.

Clean your birdbath. Enough said! And if birds aren’t visiting it, try an inexpensive, solar-powered fountain. Birds like noisy water, one ace gardener told me.

Do your weed control. Thistle seeds are blowing in the wind, my friend, and they’re not bringing answers. If we’re lucky enough to get a soaking rain, get out there afterward and dig some things up by the roots.

Speaking of digging: If you have a new bed planned, begin to break that soil or turf up and walk away. Yes, I said walk away. I learned about this technique by having hideous clay and being lazy. If you just bust through that mat of roots and clay, and then leave it exposed for a week or three, the next digging session will be easier, because time, sunshine and (we can hope) rain will have continued to break it down. The same goes for digging holes for new shrubs or trees.

Begin to use fall fertilizer for shrubs and perennials. Plant food that’s specific to fall tells plants it’s time to wind down blooming and sink their roots deep while they can; it continues to feed microorganisms that help make soil nutrients available to plant roots. I’ve had great success with Yum Yum Mix Winterizer, developed by a Santa Fe landscaper.

Clean the garage. Yes, I know, worst chore ever. Garages have become our culture’s oubliettes, where we toss old stuff and interrupted projects to forget about them. But do you really want to do this chore when it’s crummy weather? Instead, tackle it now, when you’ve got a three-day weekend coming up and might even have some daylight to complete something you half-finished. Find the rake. Sharpen the shovels. Evict the chaos. Overwhelmed? Tackle one small area at a time — or hire it done.

Wash the windows and screens. Second worst chore ever! But open-window season is coming, along with trees-dropping-everything season. Again, divide and conquer, one window at a time. Wipe out the tracks, lubricate anything that needs it and check the operation of locks, seals, and cranks, while you’ve got time to assess condition and solve any issues before wind and snow make them worse.

Stop. Breathe. Walk. Smell. Cut bouquets. Stand in the sunshine and eat a bright little tomato warm from the sun. If there’s any way you can, do the chores on this list at a meditative pace, in the beauty of the sunrise or when you can feel the cool night air rolling down from the mountains. You live here, among the rocks and sand and clay and improbable, resilient beauty. See it. No, really see it. Put down the to-do list and next-season plans for a moment and savor the abundance that is late summer. Celebrate all the things that you made a bit better, and let the rest go. Get small. Lie in the dirt and watch a bug.

This is why you garden: To remember your small and humble and glorious place. To become entwined with all that happens under the sky.

To love the world.

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