I’m still picking lots of veggies—tomatoes, eggplant, and peppers, squash, beans, chard, and herbs such as basil and parsley. Yet, fall starts in a few days and nights are already dipping into the 40s. That first frost can’t be far behind.
Here in Colorado, it’s now too late to plant most fall crops, as the short days and cold nights won’t let them mature before it snows. You can plant stiff-neck (hardy) garlic, however. Space the individual cloves about six inches apart and bury them about three-times their height. Spread a layer of mulch over the bed and relax. That’s one crop you won’t have to bother with later.
A few veggies will continue to produce after the summer ends. Parsley, chard, spinach, for example, can handle some low temperatures, as will most cabbage family cultivars, and I will enjoy them until they finally freeze solid. Tomatoes, on the other hand, are ruined by the cold, even if they haven’t actually frozen. Who wants limp and watery tomatoes? It’s better to pick any fruit that have started to turn yellow and let them finish ripening indoors. The solid green ones are too immature to ripen, but can still be used in recipes tailored specifically for them.
There are a few crops I let go to seed so I can save them for replanting next spring. I have to decide where I want next year’s parsley and cilantro, for example, so they self-sow in the right spot. Most gardeners don’t bother to save seeds from hybrid varieties, as the next generation won’t breed true. And if you grew more than one cultivar of a crop—say zucchini and pumpkins—realize that many squashes are actually the same species, in this case Curcubita pepo, and can crossbreed. You may end up with “zumpkin” next year.
We used to think that fall was a good time to amend the soil, but current research is trending toward the no-till approach. Tilling upsets the soil structure, leading to increased compaction—the exact opposite of what we are aiming for. Incorporating all that air also spurs decomposition, “burning” the organic matter we want.
Instead of digging, take a tip from Mother Nature and mulch. Arborist’s wood chips, straw, leaves—they’re all good (although research results favor the wood chips). Use what you have available. Autumn is nature’s mulch season, as foliage browns and leaves fall. All that mulch does wonderful things to the soil beneath, mitigating temperature swings, conserving moisture, and insulating roots. It also alleviates soil compaction—without us lifting a finger. Isn’t it wonderful when the best gardening practices are also the easiest?
We often feel we need to cultivate to get rid of the weeds. The mulch should take care of that, however, smothering existing plants and preventing new weed seeds from germinating. If there are still a few remaining in the spring, it will be easy to pull them out of the soft soil.
This is also a good time to get a soil test. There is plenty of time to hear back from the lab and follow their directions for adding any recommended amendments or fertilizers. Remember to wait until spring to add nitrogen, however, as it is volatile, moving into the air, and you want it available to the plants during the next growing season.
I like to make sure I’ve noted what worked well in the garden, and what I want to do differently next year. Which cultivars did we like, and which failed to perform? I found that my one of my chard varieties bolted (odd behavior for a biennial), while another did not. I don’t want to forget and reorder the one that flowered. Writing things down now means I’ll be ready to thumb through the seed catalogs when they start arriving in a few months.
As the plants finish their usefulness, or succumb to frost, you can cut them off at the soil level, shred them (if you can) and add them to a compost pile. Just don’t compost any plants infected with pests or diseases—you don’t want to reintroduce the same problem next year. For the most part, you can leave the roots in the soil; they’ll decompose in place, nourishing future crops and opening up pathways for air, water, and roots.
A few plants, mostly carrots, parsley and biennials, could overwinter and resprout in the spring, especially if your winters are mild. I like to leave the parsley roots, nestled under a blanket of mulch, for an early harvest of spring leaves. Also, parsley must be two years old to bloom, and the blossoms attract beneficial insects such as lacewings. Then, as I mentioned above, I let a few plants to go seed so I’ll have something to sow later. (I learned the hard way to encase the seedheads in a bag before they shatter.)
You can also mulch carrots, and potentially other root vegetables, and harvest them for many more months. I found a one to two foot layer of straw, covered with plastic, works well—see my 2012 post on “Carrots All Winter.” They’ll get tough, bitter, and “hairy” once the soil warms in the spring, so finish harvesting your crop by the end of February.
As much as I love gardening, I’m looking forward to the coming cold months. It’s time to garden in my imagination instead of in the hot sun.