Crocus bulbs ready to plant in the fall garden. We are in the thick of bulb-planting season. (iStockphoto)

Deep in the city, we have suffered a light frost that leaves some plants as walking wounded, others done for the year. On Saturday, I saw a hummingbird sup at a red gladiolus. The next day, the plant was blackened and gone. Whither the poor bird?

These are the dynamics of November, the month we step into another world. One day a tree is ablaze but foliated, and the next it is half-naked with its hibernal bones sticking out.

For each tree, this tipping point occurs at a different moment, depending on species and weather — the cherry trees are quick to lose their leaves, the oaks are tenacious. Willow oaks are still full and green. But there comes a time when more trees than not are done for the year, and collectively they shift the look and feel of the landscape, even if a tardy red maple is still singing its heart out.

The trees may be on the verge of hibernation, but the gardener is in the midst of one of the busiest and most vital moments in the growing year.

The most obvious task is to deal with fallen leaves, and regular readers will know my counsel here: Shred them with the mower a couple of times and rake them onto garden beds or put them in bags to be used later. There is nothing better at building the soil and keeping back winter weeds than a two- or three-inch layer of shredded leaves. The worms incorporate them into the soil, where they also sustain the beneficial microbes that inhabit the underworld and feed our plants in turn.

Many winter weeds have already germinated, by the way, and after a few years of looking at the autumn soil, you can discern the difference between the tiny scalloped leaves of the henbit and the feathery seedlings of a keeper such as nigella or the rosette of the poppy.

If you don’t cover open soil now with mulch — it’s getting late for sowing a cover crop — you will have a mess of weeds come March, when your attention should be focused on the first daffodil blooms. And we are in the thick of bulb-planting season — or should be. I once planted daffodil bulbs in early January, and they bloomed magnificently, as if I had placed them in the warm loam of October, spoon-fed them kelp meal and sung lullabies to them. But I don’t recommend waiting until the new year. Once the ground freezes, you’ve had it. And bulbs don’t keep well — they are delicate bundles of life.

Being a bit late with bulb planting has its advantages: Places that sell bulbs, especially the mail-order catalogues, tend to offer deep discounts as November progresses, though the selection is diminished.

Before the price drop, I ordered what I thought was just a few dozen (mostly daffodils), but when they arrived they were in a large and heavy cardboard box containing 600 bulbs. I don’t remember asking for so many, but I have come not to trust my perception of reality when it comes to buying plants.

All of my daffodil bulbs should be planted by Thanksgiving so that I can devote the first couple of weekends in December to the tulip planting. There is an outside chance in Washington that the ground might freeze by then. The risk is slight, but it’s best to develop the mind-set of the farmer: Plan for a job, but if the weather doesn’t cooperate, find some other work to keep the whole enterprise moving forward. I don’t place a lot of stock in sophisticated weather forecasts, especially seasonal outlooks, so I thought I might as well turn to the 2017 Old Farmer’s Almanac. It told me that in the first two weeks of December, the weather will progress from sunny and warm to showers and mild, to rain and snow, and then to sunny and mild. That seems to cover the bases.

If you are unfamiliar with the Old Farmer’s Almanac, it is a handy, 272-page manual that contains such disparate information as a planting calendar for crops, tidal charts, astronomical tables and the gestation period of livestock. The compendium dates to 1792, contains ads directed at retirees, and makes you feel that you are either in an Eisenhower-era flashback or something far older, such as a log cabin, wearing something that had been shot with the musket over the mantel.

But if you were in a log cabin in the 1790s, the almanac would function as the Internet does today and sate the same human desire for a single locus of entertainment, knowledge, variety and other pleasant distractions to while away the dark winter hours.

The almanac promises periods of mildness through the winter, not such a risky outlook in the Mid-Atlantic region. It is in those moments of thawing and warmth that you can get a lot of work done in the business of assembling garden structures — fences, gates, compost bins, arbors and walls. If the ground is not frozen, you can dig the holes for fence or arbor posts. Once they are in, it doesn’t matter if the ground hardens with freezes: You can finish the aboveground elements on those cold but still and dry winter’s days. Just don’t work in wet growing beds — you’ll squish the soil (and all those lovely earthworms).

Come March, you’ll have few weeds, enriched soil, the first bulbs and smart new garden structures. I’m looking forward to winter already.

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