Helen Simpson, from the Mushroom Shed, tells you all you need to know about growing basil. She has also written articles about growing brassicas, chilli, coriander, cucurbits, garlic, ginger & turmeric, mint, raspberries, rhubarb, strawberries, tomatoes and lesser known herbs.
One of the most popular summer herbs is basil – well known for its wonderful flavouring properties and aroma. It is the key ingredient in pesto and also mixes well with tomato based dishes. It originally came from India, where it was a sacred plant, with Holy or Tulsi Basil being highly revered and thus planted around temples and homes.
There are many types of basil, including various hybrids. Most are annual, with a few being perennial. Some of these varieties are listed below:
- Sweet Basil: The most commonly known basil in Australia, with bright green oval shaped leaves and strong aroma. An annual.
- Genovese Basil: Almost indistinguishable from Sweet Basil, but the leaves are slightly larger and darker. Traditionally used in Italian pesto. An annual.
- Dwarf Greek Basil: Compact, stocky plant with smaller leaves than Sweet Basil, but a similar flavour. Slightly hardier than Sweet Basil, but still won’t survive winter.
- Purple Ruffles Basil: The taste is similar to Sweet Basil, but the colour is a deep maroon and the leaves are heavily ruffled. An annual.
- Thai Basil: Strong liquorice/aniseed fragrance and flavour. Used in Thai and Vietnamese recipes. The leaves are smaller and more pointed than Sweet Basil and the stem has a slight red colour. An annual.
- Lemon Basil: Becoming more popular, with a lemon flavour and fragrance. Pointed green leaves. An annual.
- Cinnamon Basil: Slightly spicy, with a cinnamon scent and flavour. An annual.
- Sacred, Holy or Tulsi Basil: One of the more difficult basils to find. People who know the plant from India can dispute the authenticity of the sacred basil grown in Australia and it appears that different versions of the plant exist. I am yet to find a plant that is ‘the real Tulsi’ and would value any input from readers! The plant grown as Sacred Basil in Australia tastes very different from Sweet Basil, and has a tougher, furry leaf with a dusky pink tinge. An annual, with medicinal properties, and can be purchased as a tea.
Perennial Basil comes in many different forms, is usually a ‘cross’ of two varieties, and has a stronger, sometimes woody stem. Some have green leaves, some green with red speckles, others quite purple leaves (eg: African Blue Basil). Generally they flower prolifically but do not produce seeds, so they need to be propagated from cuttings.
You will find out exactly how perennial your plant is with the first frost – many will survive the cold, but frosty weather or excessive cold will see them disappear. On occasions, they can re-sprout in Spring, even if they look like you’ve lost them over winter.
The best way to grow perennial basil is in the warmest part of your garden. Or grow in a pot which can be moved closer to the protection of the house over winter.
Growing from seed
Basil is easily grown from seed in Spring and Summer. It generally grows quickly and strongly. However, watch out for snails and slugs who love basil too: a hungry snail can devour a plant in a few hours.
Grow basil in a clump – the plants tend to hold each other up rather than flop over.
Basil enjoys heat and sun. However, watch out for excessive heat as plants wilt if not given sufficient water. May usually sees the end of basil for the year as the weather gets too cold. Re-plant again in October.
Around North East Melbourne, basil usually grows to 40cm. You can make a plant bushier by pinching out the top leaves on a stem, which will then force the stem to divide in two and grow more leaves. Harvest every week or so once the plant reaches 10cm, always leaving some stems and leaves so that the plant continues to re-grow.
Basil is not a good herb for drying; instead, freeze or store made up as pesto.
And finally …
Whilst most basils are annuals, I have seen basil successfully ‘wintered’ by bringing a pot of basil inside and placing in a sunny window over winter. Your house will need to be reasonably warm to do this.