Growing Herbs

Culture of some popular herbs

Parsley Petroselinum sp.

Parsley is a hardy biennial plant but is best grown as an annual for culinary use. Seeds should be sown indoors at least 8 weeks before the last frost. Soaking for 24 hours to soften the seed coat may speed up germination which tends to be slow and irregular. Plant parsley in loamy, moist soil which is fairly high in nitrogen. Full sun is preferable but parsley will tolerate some shade. It is ideal for indoor culture in a bright, sunny window and prefers a deep pot to accommodate its long taproots.

Basil Ocimum basilicum

Basil is an annual which reaches maturity approximately 85 days from seeding. Seeds germinate in 7 days and produce a plant about 46 cm (18 inches) tall. Basil prefers warm temperatures, a light soil rich in humus and a regular supply of water. The tips of the shoots should be pinched off to prevent flowering as it is the young leaves which are desirable for culinary use.

Chives Allium schoenoprasum

Chives are the smallest members of the onion family. They are perennial and can be grown from seed or from divisions of the clump of tiny bulbs. In good soil with plenty of humus, chives grow rapidly to a height of 20 cm (8 inches). They are ideally suited to pot culture in a bright window.

Dill Anethum graveolens

Dill is an annual herb growing readily from seed. The seeds should be sown directly into the soil as they do not transplant well. They germinate in 10 days to 2 weeks and mature in 70 days to a plant 61 cm (21 feet) tall. Dill thrives in full sun and rich moist soil.

Sweet Marjoram Majorana hortensis

Marjoram is a perennial plant but is not winter hardy in our climate. Soaking the seeds for 14 hours before planting is recommended. They are slow to germinate and should be started indoors 10 weeks before planting out. The most flavourful leaves will be produced on plants grown in full sun, in gritty, barely moist soil with little nitrogen.

Mint Mentha sp.

There are at least 20 species and many varieties of mint. It is a hardy perennial which dies to the ground in winter. Mint may be grown from seed but germination is poor. The usual method of propagation is from rooted cuttings. Mint does well in moist, peaty soil and tolerates considerable shade. Once established it will require root pruning to keep it within bounds.

Rosemary Rosmarinus officinalis

Rosemary is a perennial plant but is usually wintered indoors in our climate. It can be grown from seed but germination and growth are very slow. The usual method of propagation is by rooted cutting. Rosemary produces more aromatic leaves when it is grown in poor, dry soil. It does well indoors when grown in a large pot in a sunny but cool location. Too much heat may cause the leaves to drop.

Sage Salvia officinalis

Sage is a hardy perennial which dies back to the ground in winter. The preferred method of propagation is by rooted cuttings as seed germination is very slow and irregular. Sage prefers sandy soil and full sun. It forms a bush 46cm (18 inches) tall.

Thyme Thymus sp.

There are more than 60 varieties of thyme of which thymus vulgaris is the most commonly used in food. It is a perennial plant which is almost evergreen in our climate. Winter mulching is recommended. Thyme may be grown from seed or cuttings. The easiest method of propagation is by tip layering (rooting of a stem by laying it on the ground and covering a portion with soil). Thyme is a bushy, creeping plant which produces the most flavourful leaves if grown in poor, relatively dry soil.

Pests

The essential oils which give herbs their flavour are really the plant's insect-repelling strategy. As a result, herbs have very few pest problems. Rosemary, thyme, sage and mint are thought to repel cabbage butterflies when planted near the cabbage patch and chives may discourage aphids when planted with lettuce and peas.

Drying

Drying is the best and simplest way to preserve most herbs. Certain conditions are necessary for success:

Darkness
Good air circulation
Dryness
Heat (preferably)
A place where they will not be disturbed for 10-14 days

Dried herbs should be stored in glass jars with tight fitting lids in a dark, cool area.

Freezing

Some herbs do not dry well. Chives tend to taste like grass, parsley loses its flavour and tarragon becomes sweet but loses its true flavour. These herbs should be frozen.

Differences between herbs and spices

Spices are defined as the buds, leaves, seeds, roots or bark of aromatic, pungent tropical or subtropical plants. Generally, spices are hot on the tongue or, put another way they irritate the inside of the mouth. This is true of all spices, not just pepper, ginger and cloves but also cinnamon and nutmeg. Herbs do not.

Toronto Master Gardener Factsheet