“Do I really need to know about vegetable families?” asked a friend with little interest in Latin names. Maybe not, I thought. After all, she grows a great garden. And maybe I’m just lured in by the beautiful order of the subject.

To botanists who classify all our crops, they’re grouped not by their fruits or leaves but by their flowers. The brassicas, such as cabbage, broccoli and turnips, have cross-shaped blossoms, hence their family name Cruciferae, which means “cross-bearing.” Umbelliferae such as carrots, celery and dill have umbrella-shaped flower clusters. Cucurbitaceae such as cucumbers, squash and melons have large showy trumpets that are either female or male. The onion family (Liliaceae), tomato family (Solanaceae) and legumes (Fabiaceae) likewise hoist the floral emblems of their clans.

For me, getting to know plants as families is a good way to learn how to grow them, because related plants have similar needs. Grouping them in your garden plan makes it easier to give them the right conditions, and to watch out for shared problems. It enables you to practice crop rotation, which is a yearly gerrymandering of neighborhoods with the goal of giving every family a new territory. Pests and diseases tend to affect family groups, so by moving to a spot where no relative grew the previous year or two, a plant can often be spared ills that would otherwise lie in wait for it in the soil.

Rearranging the garden in large blocks works fine for these major families, but smaller ones, or single crops with no major culinary kin, can seem hard to place. The Compositae, also called Asteraceae or the sunflower family, are a motley group of species including lettuce, endive, chicory, tarragon and artichokes. Beets are close cousins to spinach and Swiss chard. The sweet potato, which is related to the morning glory, is a loner in the garden that needs plenty of room. Corn stands alone, too, unless you also grow amaranth. Sorrel and rhubarb are both kin to buckwheat.

Each of these outliers requires a strategy, but they aren’t hard to fit in. Perennials such as tarragon, asparagus or the vast number of common herbs related to mint obviously need a well-chosen spot where they can stay put. Bay, a myrtle relative, needs a large space in warm climates where it becomes a tree. Lemon verbena is grown as an annual in climates where winters are cold.

Radicchio brassicas. (Barbara Damrosch)

Big players from small families such as lettuce, spinach and beets can be tucked in wherever you can, especially if they’re being grown as quick crops. A patch of cut-and-come-again lettuce or a row of baby beets can be sown in a spot where a spent crop has been harvested. A colorful row of radicchio would be fine mixed in with brassicas. It’s a dance, a game you play to keep all the beds full and bountiful, making the most of the space you’ve got. After a while it becomes habitual, with the garden an ever-changing village where any good plant can find a home.

Tip of the week

As part of the pre-spring cleanup, ornamental grasses should be cut back before fresh growth emerges from the crown. The old top growth should be cut back at about two inches above the soil line. Hedge shears work well. Work on clumps in sections. On hilly sites, begin from the uphill side for a better view of the cut.

— Adrian Higgins

Damrosch’s latest book is “The Four Season Farm Gardener’s Cookbook.”