Growing medicinal plants may be more time-consuming than buying them, but it brings with it the unique pleasure of producing your own herbal remedies. Many medicinal herbs are easy to grow and will flourish indoors, on a windowsill, or in the garden, providing a year-round supply of fresh, sweet-smelling natural medicines.
The Medicinal Herb Garden
Planning an herb garden depends on a range of factors including the space available, exposure, soil, conditions, and climate. As a starting point, details of ten of the most common and useful medicinal plants for growing in temperate climates are given in the chart below. Some of them, such as thyme (Thymus vulgaris) and sage (Salvia officinalis), may be grown indoors. A number of other medicinal herbs, including German chamomile (Chamomilla recutita), lady’s mantle (Alchemilla vulgaris), and lavender (Lavandula officinalis) also grow well in a temperate climate and are well worth cultivating. If in doubt about how to care for plants or what will grow well in your garden, consult a nursery.
Choose a range of hardy herbs to grow in your garden that will establish themselves easily and produce plenty of foliage that can be harvested. Plant exotic or less hardy herbs in sheltered sunny sites or in containers.
Many medicinal plants such as peppermint (Mentha x piperita) or bay laurel (Laurus nobilis) can be grown in pots, hanging baskets, or window boxes. Care must be taken to prevent them from drying out or becoming pot-bound (when the plant becomes too large for the container). Less hardy plants should be moved to sheltered sites or indoors during winter.
Growing Plants Under Cover
Sheltered gardening offers the opportunity to grow more unusual plants. Use the greenhouse to cultivate exotic plants, such as lemon grass (Cymbopogon citratus), for medicinal and culinary use, as well as for growing seedlings to be planted outdoors. Tender plants, such as holy basil (Ocimum tenuiflorum), thrive indoors, and some indoor plants, such as aloe vera (Aloe vera), have the added advantage of absorbing polluting chemicals from the air.
Buying Medicinal Herbs
Reputable herb nurseries are the best place to buy herbs when particular varieties or species are required. Be clear about what plants you want before visiting the nursery. When buying for medicinal use, purchase the standard medicinal, rather than an improved or ornamental variety.
Bear in mind the following points when planning the garden and choosing herbs. Site The majority of medicinal plants prefer a sunny exposure and moderately well-drained soil. It is possible to improve a site, for example by planting hedges as windbreaks. Choose sheltered, sunny corners for delicate and half-hardy herbs, and avoid planting on land formerly used for industrial purposes, which may be contaminated.
Some plants tolerate only very specific temperature ranges, and many herbs, such as rosemary (Rosmarinus officinalis), are only half-hardy and will not survive exposure to deep or long periods of frost. Protect tender and halfhardy plants from the wind to avoid the windchill factor. Spring is the best time to plant most herbs. Wintering plants in a greenhouse or cool indoor site is often the only way to keep subtropical plants in cool temperate climates, while other herbs will thrive indoors all year round in a warm, sunny position.
Soils vary greatly depending on the proportions of sand, silt, and clay content. Sandy soils drain easily and need feeding, while clay soils can become waterlogged and require drainage.
Pruning is used to remove dead wood and improve the shape, size, and quality of growth. It is an important garden activity and needs to be done correctly for different woody plants to benefit—check the best time of year for each plant. Deadheading plants, especially shrubs, encourages fresh growth. Pruning and tidying the garden regularly also reduces pests and diseases.
Water well after planting and then, if needed, once a week (rather than a little each day) in the morning or early evening. Do not overwater as many herbs produce medicinally active constituents in dry conditions. Water dry potted plants thoroughly before planting.
Weeding & Fertilizing
Weeding is necessary since weeds compete with other plants for nutrients and water. Keep beds and containers as free from weeds as possible. Most medicinal herbs should not be fed or mulched as this tends to reduce their therapeutic strength. However, sandy soils should be fed with a good-quality fertilizer to maintain the nutrients in the soil.
Pests & Diseases
Use only organic methods to treat pests, diseases, and insect infestation. Aphids can be eradicated using soapy water or water in which garlic skins have been soaked for 2 days. Separate any infected plants to prevent further contamination.
There is a wide variety of propagation methods. Choose the one most suited to the plant. When planting, prepare the ground in advance, taking into account the requirements of the individual plant, and the soil, site, and time of year, as well as the anticipated size of the mature plant.
Seeds can be sown either in containers or in prepared soil in open ground. It is important to time the sowing of seeds to enable seedlings to be planted outdoors when weather and soil become sufficiently warm. Annuals and biennials can be grown with ease from seed and will grow vigorously throughout the summer. Check the germination requirements of perennials before buying seeds, as some varieties germinate easily, while others, such as Siberian ginseng (Eleutherococcus senticosus), can be far more difficult.
This is one of the most popular methods of propagation. It is suitable for woody perennial herbs. Cuttings are usually taken from the stem, although some plants may also be propagated from roots. Choose young, healthy plants and take the cutting just below a leaf and stem joint using a clean, sharp knife. Strip off the lowest leaves and dip the stem in hormone rooting preparation before inserting it in suitable soil mix. Some plants are very difficult to propagate this way, so check before attempting this method.
This is an easy way to propagate plants that form clumps. Divide spring-flowering herbaceous plants in autumn, and autumn-flowering herbaceous plants in spring. Carefully lift a mature plant, divide it into smaller sections, and replant both the new and the mature plant.
Plants from Produce
Purchase pots of culinary herbs from a grocery or supermarket, split the seedlings into 3 to 4 small clumps, and pot them separately. Fresh roots, such as ginger (Zingiber officinale), or bulblets, such as garlic (Allium sativum), can be planted in pots or in prepared ground outside, if temperature allows.
Layering involves encouraging a shoot or stem to form roots by making a small slit in its underside and burying it, with the growing tip above ground. When the layer roots emerge, remove and pot. “Mound layering” is suitable for woody herbs such as sage (Salvia officinalis). Pile free-draining soil over the base of the plant, and when the layered stems form new roots, remove and pot.
Useful Herbs to Grow
|Plant||When to Plant||Cultivation Method||Conditions and care||Medicinal Use|
|sunny site indoors; pot up as needed; do not overwater||fresh plant gel for minor burns and wounds|
|warm sunny site; moist soil||ointment or poultice for sprains and bruises (use the leaf only)|
|well-drained or dry, stony soil in sun
|fresh leaf or tincture for headaches and migraines
|moist soil in sun; cut back after flowering||infusion for anxiety, poor sleep, and nervous indigestion; lotion for cold sores|
|well-drained soil; full sun; remove dead flower heads||cream for cuts, scrapes, inflamed skin; infusion for fungal infections|
(Mentha x piperita)
|sunny but moist site; do not allow to dry out||infusion for indigestion and headaches; lotion for itchy skin|
|sunny sheltered site; protect with burlap in winter||infusion as a stimulating nerve tonic and to aid weak digestion|
|well-drained or dry, sunny, sheltered site||infusion for sore throats, mouth ulcers, and diarrhea|
|St. John’s wort
|well-drained to dry soil with sun or partial shade||tincture for depression and menopause; infused oil is antiseptic and heals wounds|
|spring/autumn||seed/cutting/division||well-drained soil, may need a layer of gravel; sunny site||infusion for coughs, colds, and chest infections; lotion for fungal infections|