Taking good care of an herb garden results in wonderful quality and a big harvest for food and crafts. Herb gardens need good air circulation, protection from extreme weather, and adequate watering.
Herb garden woes? Water, weather, and circulation
To keep your herbs from being choked, or dulled, keep your garden away from low spots, where cold air can pool. Cold air is heavier than warm air; that’s why low areas are susceptible to frost. Poor air circulation also provides the stagnant conditions that plant diseases love, especially in humid climates. Do everything you can to ensure good air circulation.
If you must fence your garden to ward off wildlife, four legged or two, don’t make it a solid wall that will keep your herbs from getting the fresh air they need. At the same time, if your property is near the ocean — or regularly in the path of fierce winds — your herbs may need protection. Any garden site that regularly gets winds in the 15-mph range needs a windbreak, or wind barrier. Wind barriers also safeguard the soil from erosion and help keep it from drying out. A cold wind can annihilate a row of young basil plants in a matter of hours (or, if you’re lucky, just slow their growth for weeks to come). In contrast, hot winds desiccate, or dehydrate, plants, and that, too, can be lethal.
If you leave your containers of herbs sitting outside in winter, the plants’ roots aren’t protected from the cold air. As a rule, you can leave perennial herbs outdoors in containers all winter if they’re hardy to one zone farther north than your home. One warning: If you live in the far North, you may be growing herbs that won’t survive even with this coddling.
Garden flowers, vegetables, and fruits require extra water when they’re forming flowers or fruits. In contrast, herbs, most of which have small flowers and are grown primarily for their leaves, need even moisture throughout the garden season. Just as you need to water more in hot climates and less in cool ones, you need to water differently depending on the texture of your soil. Install a rain gauge and keep track of rainfall, but don’t be a slave to numbers: If there was an inch of rain in the past week but your plants clearly show that they’re thirsty, water them. If you haven’t had rain but your herbs look great, don’t do a thing except feel grateful.
Before you anticipate the horticultural version of Murphy’s Law kicking in, remind yourself that herbs are among the garden plants least bothered by diseases and pests. With help from you, they’ll grow vigorously, untroubled by plagues or pestilence.
Bugs and animals that are good for herb gardens
Biological controls are living organisms; using biological controls is based on the theory that every pest has a mortal enemy. It’s a relatively new field of long-term pest control. The controls themselves, however, have been around forever — and many of them are already sharing your zip code.
Following is a short list of beneficials that you want to keep around your herb garden.
Aphid midges: The midge larvae — tiny orange maggots — commit “aphidcide.”
Dragonflies: You need water to attract these flyers, one of the garden’s most beautiful do-gooders.
True bugs: Believe it or not, “true bugs” is the scientific name for a group of insects, which includes predatory members that attack aphids, beetle larvae, caterpillars, and thrips.
Yellow jackets: If yellow jackets nest far enough away not to sting you, leave them alone to gather caterpillars, flies, and assorted larvae for their offspring.
In addition to these small pest-control champs, some larger animals are worth having on garden patrol. It's not that you should import these helpers — they may be inappropriate for your location or sensibilities — but don’t discount the good they can do:
Bats: Forget all the scare stories about rabies — scientists say that the danger is remote — and remember that bats are champion insect-eaters.
Birds: You can forgive birds a few transgressions, such as eating the cherries and blueberries, when you remember how many bugs they eat. One estimate is that aphid eggs make up half a chickadee’s winter diet!
Skunks: Although skunks are debatable as garden ornaments, they do love grubs. Moles are also great grub grubbers if you can put up with the lawn damage they cause.
Snakes: Maybe you draw the line at encouraging snakes to dwell in your herb garden, but they’re after rodents and insects, not you.
Toads: Toads eat an almost exclusive diet of grubs, slugs, beetles, and other harmful insects. Encourage toads by chipping a doorway on the side of a terra-cotta pot and leaving it, turned upside down, in a shady spot in your garden.