It's easy to grow an indoor herb garden. Potted indoor herbs add a touch of greenery to your décor and fresh flavour to your cooking.
“Governing a large country is like frying a small fish. You spoil it with too much poking.” In this quote from his 2,600-year-old Chinese classic, the Tao Te Ching, Lao Tzu is extolling the wisdom, “Let it be.”
The same sagacity applies to growing herbs. In the garden, with a few tender exceptions, herbs are a low-maintenance delight. Pest and drought resistant, many of them thrive on neglect.
Sadly, this is not the case indoors, where these rugged outdoorsmen turn delicate and demand attention. But they’re worth it. To be able to make an herbal tea with fresh mint or to add fresh chives to your soup, salad, or sandwich in the middle of January is a joy deserving of a little effort.
Paying close attention to some of the special needs of herbs grown indoors will help you to enjoy them all year round.
Annuals such as basil should be started from seed, while perennials grow well in pots and can be moved into the house in fall and back into the garden in spring. It’s wise to acclimatize these herbs gradually to the lower light by moving them in two or three stages to progressively shadier spots in the garden.
- Use pots with a minimum 6 in (15 cm) rim diameter.
- Choose terra cotta or clay pots over plastic ones; they allow roots to breathe and are more environmentally friendly as well as aesthetically pleasing.
- Ensure the pots have holes to provide good drainage and sit them in a tray on a bed of gravel or pebbles, which should also contain water to provide ambient moisture.
- Select an organic potting soil.
- Augment soil with some sand or preferably perlite, vermiculite (see below), and a little lime.
- Ensure the soil pH is between 6 and 7.
The primary need of your indoor herb garden, once you’ve planted your herbs, is light, either natural or artificial. For best results, use a combination of both.
- Place herbs in a south-facing window where they can get at least four hours of sunlight per day.
- Turn herbs on a windowsill regularly to maintain growth symmetry.
- Maintain daytime temperatures around 18 to 20 C, dropping to no lower than 14 to 15 C at night.
- Choose fluorescent lights for seedlings and low-growing herbs.
- Try high-intensity discharge (HID) lights if you are a serious indoor herb grower; they are more expensive to buy and to operate, but they are worth the price.
- Ensure your herbs receive about 14 to 16 hours of light, with at least eight hours of restful darkness per day, if the only light source is artificial.
The second major need of indoor herbs is the correct amount of root and ambient moisture. Although herbs are tolerant of drought in your garden, the excessive dryness of house interiors during a Canadian winter can be very stressful to them.
- Water herbs thoroughly initially, and then allow the soil to dry before watering again; this can be necessary each day indoors.
- Ensure the water level does not rise above the base of the pots; herbs do not like to have wet roots.
- Perform a monthly flushing of the herbs by placing the herbs in a sink and watering completely, allowing the excess to drain away. Once the pot stops dripping, water thoroughly again. This will remove any salts that build up in the soil.
- Thoroughly water the plant first, which will increase absorption.
- Use liquid fertilizer or organic fish emulsion.
- Fertilize weekly, but use just 25 percent of the recommended amount.
What is perlite?
Perlite is a white, round pearl-like volcanic rock. It’s mined, then crushed and rapidly heated to about 1,000 C, whereupon it starts popping like popcorn. This makes the pebbles larger and less dense. Adding perlite particles to potting soil ensures the soil is well drained.
What is vermiculite?
Vermiculite, like perlite, is a mineral that is heated and blended into potting soils. But while perlite increases drainage, vermiculite does just the opposite: it helps the soil to retain moisture. Its role is to provide a timed release of water and nutrients.
How to use indoor herbs
makes an ideal after-dinner tea, being both a sedative and digestive aid; can be used in any dish to add a mild lemon-lime flavour, including fish, poultry, marinades, salad dressings, preserves, and desserts
primarily a culinary herb, popular in soups, salads, any dishes with tomatoes and, of course, pesto and other pasta sauces
with one of the highest levels of antioxidants of any plant—four times higher than blueberries—powerfully antibacterial and antiviral; popular with tomato-based dishes such as pizza and pasta, and also superb with poultry
tie in a cheesecloth bag and add it to your bath to ease muscular aches and pains; add to all pot roasts and stews; a key ingredient in bouquet garni
only good when fresh; excellent source of calcium, iron, vitamin A, vitamin C, and phosphorus; mild peppery onion flavour makes them a hit in almost any dish except dessert
What are the best herbs to grow indoors?
We asked two experts on indoor herb gardens about their favourite picks for planting indoors.
Brad Boisvert, chef/proprietor of the award-winning Amuse Bistro in Shawnigan Lake, BC:
- Grolau chives, with its strong flavour and thick green leaves, was especially developed for indoor growing
- Lemon thyme, with its exquisite flavour that is impossible to find commercially
- Marjoram (Greek oregano is preferable, but it requires more light)
- Purple sage
Pat Anderson of Valhalla Farms Herbs & Things organic farm in Duncan, BC:
- Lemon verbena
- Bay leaf
Other herbs that adjust well to indoor cultivation include:
- Fernleaf dill (a dwarf variety)
- Creeping savory
Getting rid of unwanted pests
If you’re bringing herbs indoors for the winter, try to avoid little critter passengers. With no winter cold to kill the eggs, insect pests can be a problem. If you see evidence of them, here are some suggestions to send them packing.
- Prepare some tepid soapy water in the kitchen sink or a large bowl.
- Covering the soil with your hand or a cloth, turn the pot over and swish the aerial parts of the herb in the soapy water. This will not harm the plant, but it will kill the bugs.
- Alternatively, spray the herb with the soapy water or an organic, harmless insecticide such as diluted neem oil. Be sure to get the underside of the leaves, where the bugs and eggs hide.
- Treat rosemary, which can be susceptible to mildew, with a mild solution of one part hydrogen peroxide in three parts of water, weekly or bi-weekly.
A small investment of time and money will pay big dividends. Your indoor herb garden will yield infinite delight visually, aromatically, nutritionally, and gastronomically all winter long.