(Updated March 2019)
Everyone loves the taste of herbs harvested fresh from the garden. And winter doesn’t have to spell the end of that enjoyment. Just a handful of pots indoors can supply bundles of savory herbs throughout all the seasons. All you need are some culinary herbs, a sunny window and a little TLC in the form of good soil, judicious watering and a regular supply of food.
Why grow herbs?
Aside from the convenience, growing herbs indoors can ensure your meals are packed with flavor while adding beauty and greenery to your kitchen windowsill or counter. Like houseplants, herbs provide a host of benefits, including increasing oxygen levels and purifying the air. And nothing beats the pungent smell of their fresh cut leaves.
KEY INGREDIENTS FOR SUCCESS
Light is the vital ingredient needed by all plants for photosynthesis. And herbs are sun worshippers. When grown indoors, they require a lot of natural light. Six to eight hours a day of direct sunlight is ideal, although some herbs will make do with as little as four.
The best windows for growing herbs are those that face south or southwest since they receive the bulk of the sun year round (although an east facing window can provide good light levels in the morning.) Never place herbs on the sill of a north-facing window. They won’t receive direct light.
Even with lots of natural sunlight, some herbs require supplemental lighting. Full-spectrum fluorescent lights, which most closely replicate the natural solar spectrum, can do the trick. Install these inexpensive bulbs in a light fixture, grow cart or under kitchen cabinets to give your herbs an extra boost. Place the lights close to the plants, about 4- 6-inches away.
Clearly, all plants need water to survive, but unlike most plants, herbs don’t need all that much. In fact, overwatering is one of the biggest problems when growing herbs indoors. A good rule of thumb is to let the plants mostly dry out, and then saturate them completely. Once you determine how long it takes for them to dry out, stick to a consistent watering plan. Herbs love consistency.
In particular, good drainage is crucial. Make sure there are good drainage holes in your containers and never leave plants standing in water, which leaves roots vulnerable to root rot (a common cause of plant demise.) Water your herbs at the base of the stem where it meets the soil and wait until the container has drained completely before placing it back on its saucer.
Clay pots are beautiful, but they dry out quickly. Plastic and ceramic make better containers for herbs because they are better suited to drier indoor conditions. Select pots that are no bigger than 6 inches and make sure to check on them regularly, especially if they are located near a heat source. Dry, heated air can be hard on plants.
A good organic potting soil is essential to producing healthy herbs. And a sterilized compost based mix works best. You can further amend the soil by adding in some sand or perlite to improve drainage. Once you’ve planted the herbs, turn the pots regularly to make sure the plants don’t grow in one direction.
Feed your herbs once a week with a good organic fertilizer like fish emulsion or liquid seaweed. This is an absolute necessity for plants confined to small containers where they quickly devour nutrients. In addition, fertilizer helps with good oil production, which is where herbs get their flavor.
Indoor herbs like the same temperatures humans do. Average temperatures of 65 to 70 degrees in the daytime and slightly cooler ones at night will keep them healthy and happy. However, be careful not to let leaves touch a cold window.
Unfortunately the same pests that afflict houseplants, such as white flies, aphids and scale, sometimes afflict herbs. Control pests by dipping the entire plant into a pail of insecticidal soap, making sure to wet all leaf surfaces thoroughly.
WHAT TO GROW
Chives; One of the easiest plants to grow inside, chives form little clumps of grass-like leaves that are as attractive as they are delicious. Harvest leaves by clipping the outermost ones first and working your way inwards.
Lemongrass. You can start this miniature grass with the lemony scent in a vase or glass, with just a few inches of room-temperature water. Transplant it to a pot once it has sent out roots and stalks. The most edible part of the plant is at the bottom of the stalk, so harvest older stalks first and snap them off close to soil level.
Mint: A gardener friend of mine once said to me when I was contemplating planting mint in my garden, “Once you have mint, you always have mint.” No truer words. It quickly invaded all neighboring space. Indoors, the same holds true. Plant your mint in its own separate pot.
Parsley: You can easily grow both flat- and curly-leaved varieties of this herb in a sunny window with minimal care. Parsley likes humidity, though, so mist it regularly or set it on top of pebbles in a tray with a small amount of water to increase moisture levels around the plant.
Basil: this aromatic herb likes evenly moist soil. Pinch the bloom stems back to keep the plant looking neat and to concentrate flavor in the leaves. Basil has a wide variety of flavors, colors and size of foliage. ‘Sweet’ (Nufar) is the most common variety used in salads and sauces and as flavoring for fish and meat.
Lemon balm: Used since ancient times as an herbal remedy, lemon balm is a close cousin to mint and just as voracious. Plant this easy-to-grow herb in its own container and snip stems regularly to keep the plant looking neat.
Oregano: This heat and sun-loving herb thrives in all-day sunlight where it will gradually form a bushy mound of oval green leaves. Pinch the flowers off as soon as they appear to keep the herb’s flavor concentrated in the leaves. Greek oregano, O. vulgare hirtum, has a much more pronounced flavor than common oregano, O.vulgare.
Rosemary: Like thyme, this herb likes to be kept on the dry side. Too much water will damage the roots and cause the plant to brown and die. Too little water produces the same symptoms. Dry, brown rosemary plants are a common problem when growing the plant indoors, making this one of the more tricky herbs to grow. The plant is also very susceptible to powdery mildew, so make sure it has good air circulation.
Sage: There are many varieties of this fuzzy-leaved species, but for cooking, the common garden variety Salvia officinalis and its cultivars are hands down the best. The plant can get pretty tall- up to 24 inches, so look for dwarf varieties or keep it compact by regularly harvesting stems.
Thyme: As soon as the plant has foliage, you can begin enjoying this popular Mediterranean herb. Simply snip off the stems, rinse them and remove the leaves, crumbling them gently between your fingers. Thyme is drought-tolerant, so it should be watered only after the soil has mostly dried out. Like all herbs, it requires good drainage.
Of course there are many other delicious herbs not mentioned here that are also easy to grow indoors. Check out your local garden store or supermarket for inspiration.