Basil—a fresh favorite that thrives at home: explore different varieties and learn how to grow and care for it
Basil needs consistent warmth, moisture, and airy, nutrient-rich soil. Urban gardeners will get the most reliable basil harvest from a self-watering pot on a covered balcony. Check out these tips to help your basil thrive!
Basil is used in cooking by picking fresh leaves; young flowers are also edible. However, it’s best not to let basil bloom, as it can become bitter. That’s why you should pinch and harvest your plant regularly. You can also freeze basil, but drying it isn’t recommended, as the flavor will fade.
Basil plants grown in Finland (Ocimum basilicum) are annuals. The genus Ocimum includes 150 species. That’s why there are dozens of basil varieties and leaf shapes: large, small, curly, and even red. Basil’s aroma comes from various volatile oils, and their relative amounts influence the scent of the plant. Flavors range from a mild fruitiness to lime, cinnamon, or even a strong peppery kick.
It’s worth saving basil seeds. They remain viable for a long time.
How to grow basil? Here’s how to succeed!
Light and location
Basil prefers a warm, bright spot, such as a sheltered greenhouse or a glazed balcony. In southern Finland, basil can thrive outdoors as well, if the location is sufficiently sheltered, like a sunny southern slope.
Outdoors, you can boost warmth by planting seedlings in black plastic mulch. A fleece tunnel or a raised bed also helps retain heat. For container growing, self-watering pots are ideal.
Basil seed starting
Sow seeds in early April in a small box with 3–4 cm spacing or plant 2–3 seeds per pot. Before sowing, moisten the soil and tap it gently to settle. Cover with a thin layer of sand, peat, or vermiculite, then cover with plastic. Keep the soil consistently moist by misting. Basil germinates best in light. A good germination temperature is around +20°C.
Pricking out basil seedlings
Prick out the seedlings when they are a few centimeters tall. Transfer them into pots about 6–7 cm in diameter. If you have two seedlings per pot, remove the weaker one.
Hardening off basil
Begin hardening off the seedlings outdoors from mid-June, a couple of hours at a time. Only move them to their final location when nighttime temperatures remain above +15°C. In open ground, leave 30–40 cm between seedlings and rows.
Pinching basil
Pinch the seedlings once they have a few true leaves in addition to the cotyledons. Leave a few pairs of leaves on the plant. Keep pinching regularly, so the plant branches out, produces new leaves, and doesn’t bloom.
Growing medium
Plant basil in rich, nutrient-filled, well-draining soil or a grow bag. In containers, use fertilized and limed peat-based soil.
Watering basil
Water basil at regular intervals, keeping the soil consistently moist but never waterlogged. Excess water, especially at night, can cause root rot if the weather is cool. It’s best to water seedlings during the day.
Fertilizing basil
In open ground or in a greenhouse, mix compost into the soil. Alternatively, apply a general fertilizer in spring. Apply lime following package directions. You can substitute lime with ash, using a few deciliters per square meter.
Fertilize potted basil with a mild liquid plant food or fertilizer spikes about a month after planting.
Basil species and varieties
- Basil, Ocimum basilicum. Among this species, you’ll find cultivars, forms, and subspecies such as:
- ‘Genoveser’. Large-leaved, fast-growing, aromatic, and tasty.
- ‘Opal’. Dark purple-red leaves with a strong, refined flavor.
- ‘Green Ruffles’. Large, pale-green, crinkled leaves with an anise-like taste.
- ‘Citriodorum’, lemon basil. Smallish, lemon-scented leaves, also goes well in desserts.
- ‘Cinnamon’, cinnamon basil. Large plant, mildly cinnamon-flavored.
- ‘Licorice Basil’. Mild anise or licorice flavor. Looks lovely in flower beds. Grows to about 40 cm in height.
- O.b. var. thyrsiflora, thai basil. A sturdy, strongly flavored variety, used fresh.
- O.b. subsp. minimum, Greek basil. Small-leaved, bushy, and aromatic.
Other basil species:
- American basil, Ocimum americanum. Originating in the Americas, lime-like aroma, height around 50 cm.
- Holy basil, Ocimum tenuiflorum. Native to India, strong sweet aroma, abundant flowering.
- Clove basil, Ocimum gratissimum. Native to the Caribbean, woody stems. Overwinter indoors.
