Plant of the Month: Basil

Plant of the Month: Basil


“Pounding fragrant things – particularly garlic, basil, parsley – is a tremendous antidote to depression.”

Patience Gray, English food writer (1917-2005)


Despite the fact that many people associate basil with pesto or bruschetta, basil did not originate in Italy, or even the Mediterranean region. Basil originates from Asia. Like many plants of Asian origin, it was brought to Southern Europe on the trade routes and gradually moved northward and westward.1


Basil (Ocimum basilicum) is a warm-climate herb.  Many of the plants are annuals, but there are some hardier (not frost tolerant) perennial basils. If you’ve ever tried putting fresh basil in the refrigerator, you may have noticed how quickly it wilts and begins to rot. Basil does not like cold weather.

Basil is a member of the mint family, it has square stems. The highly aromatic leaves grow in opposite pairs. They have curved edges and a point at the tip of the leaf.2 The most popular type of basil is “sweet basil”, the variety most often sold as a herb in supermarkets and garden centres. However, there are more than 60 varieties of basil in the world.1 Basil is commonly thought to have green leaves, but there are varieties with dark red, almost purple leaves. That flavour of basil can be sweet and mild, slightly licorice, or it can be quite strong. There are varieties of basil with hints of other flavours; for example Basil ‘Lemon’ or Basil ‘Cinnamon’.


The leaves of basil are best eaten fresh; they tend to lose their potency when they are cooked. Dried basil is generally added to a dish sooner than fresh basil: it take time to impart its flavour to other ingredients. Fresh leaves can be frozen in ice cube trays with water or simply placed on a baking sheet and put in the freezer for about 30 minutes, until the leaves are completely frozen.

Basil, sometimes called “the king of herbs”, is used in Mediterranean dishes, where the sweeter softer basils are favoured, and in dishes of Asian origins, such as those from India, Thailand and Vietnam, which often make use of the more robust Thai-style basils. The colour of the purple stems of some Thai basils intensifies as it is cooked.


Basil has anti-inflammatory and antibacterial properties. This means that it is used in a wide range of treatments in traditional medicine: head colds, warts, worm infections, heart disease, diabetes, arthritis, anxiety or depression, and age-related memory loss; even as a preventative against cancer. 4 5

Many of the compounds contained within the leaves of basil can be lost in the drying process so it is best to use fresh basil leaves where possible.5

OTHER BENEFITS: Skin Care and Insect Repellent

Basil has long been used in the skincare routine of women in India and other parts of Asia.6
Basil leaves can be rubbed on the skin as a form of insect repellent.7


Different varieties of basil grow to different heights. Most people know basil as a slightly straggly plant, but one variety, Basil ‘Greco a Palla’ (literally Greek ball), grows into a neat ball-shape. Most varieties are annual. but some are perennial. These are usually taller growing varieties with thicker, tougher leaves. Be sure to refer to the seed packet for information about the size and other features of the plants. Some varieties of basil may need staking.

Seed can be sown directly where you want the basil to grow; or you can raise seedlings in seed trays, punnets or little pots. In warm conditions, basil seed should germinate in about 7-10 days. The soil, for annual basil, needs to be quite rich to keep it growing well.

At this time of year (February), grow basil in a pot rather than in the ground, That way, as the days get cooler, you can move your pot into a sheltered, sunny position, in front of a north- or west-facing wall or fence, to extend the season. We don’t have frosts, and grow our basil in pots in front of a west-facing Colourbond fence: in this way we have had basil in leaf well into winter!

Basil is a leafy plant, so it requires plenty of nitrogen; but be careful: too much will result in a weak, sappy plant which “pests” will love! Start harvesting from your basil plant when it is about 15 to 20 cm tall, and has at least five sets of true leaves (that is, 10 basil-shaped leaves).

As the weather cools, basil will go into flower, which the bees and other pollinators will love! You can extend the season by removing the flowering spikes as they start to form. Sooner or later, the plant will try to reproduce itself and the flower spikes will become more numerous and appear more frequently. When this happens, allow the plant to flower then allow the flowers to die naturally while still on the plant. This way you can collect seeds for next season’s basil for yourself or to swap with friends!

Next spring and summer, start a few basil plants every two or three weeks so that you have a continual harvest over many months.

BASIL IN THE PSW SEEDBANK (your seed bank)

The links above are to the PSW Spring catalogue, which is currently closed but the descriptions are stll relevant.. Please note: seeds are for sale to PSW members only.
Thank you.

Until next month
Lynne (PSW Seed Savers Team Coordinator and Custodian of the Seed Bank)


This article is for gardening information and general interest only. Being neither a herbalist nor a qualified medical practitioner, I cannot give any medical advice on the use of basil, internally or externally. Readers of this article must do their own research before using basil for any purpose other than as a garden plant.


  1. McCormick, About Basil, Uses, Pairings and Recipes
  2. San Diego Zoo, Sweet Basic: Ocimum basilicum
  3. Hazel Wheaton, 11 Mistakes You May Be Making with Fresh Basil
  4. Rx List, Basil
  5. Nourish by WebMD, Health Benefits of Basil
  6. PharmaTutor, Basil (Tulsi) in Cosmetics
  7. Wilsons Garden Center, Herbs That Repel Bugs