Basil

Ocimum basilicum

Introduction: Basil is a native of southern Asia and many kinds are grown there. The name comes from the Greek word “basileus” meaning “king” as it is often considered the king of herbs.

Basil is without doubt the most important culinary herb in my kitchen, In fact I think of it more as a vegetable than as a flavoring herb and grow it like spinach. I can use as much as I can grow, because I make any surplus into pesto and freeze it for winter use. Pesto is always quite expensive to buy, so this can be a very valuable crop.

Nutritional content: Basil contains some powerful antioxidants that give it anti-cancer activity. It may also help to lower cholesterol. It contains about 130 calories per pound.

Crop value: Basil is easily grown, very flavorful and I love it. Consequently I rate it as one of the most essential crops and grow it in vegetable sized (as opposed to herb sized) quantities.

Ease of growing: Basil isn’t a very demanding crop so long as it gets warm weather. In the right circumstances it will often grow like a weed. If it doesn’t get warm weather it is not so easy; it really doesn’t like the cold.

Climate: Basil is a short lived perennial in tropical climates, but anywhere the temperature drops below 60˚F it has to be grown as an annual.

Soil

pH 5.0 (6.0-7.5) 8.0

Basil prefers a rich, light, well-drained soil.

Soil preparation: Basil can produce a lot of foliage in the course of a summer, but needs plenty of nutrients to do so. Incorporate 2˝ of compost or aged manure into the top 6˝ of soil before planting.

About Basil   Seed facts Growing temp: 60 (75 – 85) 90˚F Germ time: 5 – 10 days Seed viability: 8 years Weeks to grow transplant: 4 – 8   Planning facts Hardiness: tender Germ temp: 60 (70 – 85) 90˚F Plants per person: 4 Plants sq ft: 3 – 4 Plant height: 6 – 18: Plant diameter: 6 – 12˝   Planting Start in: 4 – 6 wks before last frost Plant out: 2 wks after last frost Direct sow: 2 – 4 wks after last frost   Harvest facts Days to harvest: 60 days Harvest period: 1 – 3 months Yield per plant: 4 oz

Planning

Where: Basil is unhappy if it isn’t warm, so in cooler areas it should be put in the warmest and sunniest spot in the garden (and sheltered from cold wind). If even this isn’t warm enough, then grow under cloches.

As you are only growing basil for its leaves, it can be grown in part shade. However it won’t be as productive as when in full sun. 

When: Basil is slow to get established if the weather is not warm, so the first plants of spring are usually started indoors, about 6 weeks before the last frost date. Don’t plant it out until at least 2 weeks after the last frost, when the soil has warmed up (to at least 60˚F and preferably 70˚F). If you are in a hurry you could hasten this process with cloches or plastic mulch.

Succession sowing: Basil can be harvested for quite a while if you use the right technique, Nevertheless it is common to make several sowings over the course of the summer, perhaps every 4 – 6 weeks or so (these later plantings are usually direct sown). This will give you a continuous and abundant supply of new plants and will ensure you never run out of pesto.

Planting

Indoors: The first basil is usually started indoors, in flats, cell packs, soil blocks or plug trays. Sow the seed in ¼˝ deep furrows or scatter it on the surface and then covering with a ¼˝ of sowing mix. When the plants have at least 2 (and up to 4) pairs of true leaves you can transplant them into the garden (they transplant quite easily).

While the plants are indoors you should go easy on the watering and keep them well ventilated to avoid damping off fungi.

Outdoors: If the weather is warm enough it’s better not to mess with starting indoors, just sow directly into the garden. Plant the seed ¼˝ deep and keep moist and well weeded until the plants are growing well. The seedlings are easy to recognize by the pair of distinctive D shaped cotyledons (seed leaves).

Direct sowing is a lot less work than raising transplants, but you won’t get a crop until a little later. I use both methods, growing my earliest plants from transplants and later ones by direct sowing. Try sowing some seed when you transplant your first basil seedlings into the garden.

Spacing: The spacing for basil varies from 6˝ – 8˝ – 12˝ apart, depending on the variety and how big you want the plants to get. If you want the plants to grow into 24˝ tall bushes you may even plant them 18˝ apart. I find the closer spacing works well because I harvest prune by pinching the shoots off frequently.

Care

Warmth: The biggest problem with basil is its dislike of cold weather. It just won’t thrive if the summer isn’t warm. Fortunately this isn’t a problem in most of North America.

Weed: Keep the plants weeded at all times, but especially while they are young.

Water: Basil must have evenly moist soil for maximum productivity and best flavor, so water whenever it gets dry. Plants sometimes respond to drought by bolting.

Fertilization: If you are repeatedly harvesting from the same plants, you should give them a liquid feed (compost tea or liquid kelp) every couple of weeks. It’s probably best to use this as a soil drench, rather than as a foliar feed, as you want to keep the leaves as clean as possible.

Mulch: This is beneficial in hot weather as it conserves moisture and suppresses weeds.

Pruning: The growing tips should be pinched out when the plants are 6 – 8˝ tall (this is actually the first harvest). This causes them to send up two growing tips, making the plants bushier and larger. It may also delay flowering. If you carefully harvest prune the plants, you can harvest from them for weeks, or even months.

Problems

Frost: If frost threatens you can try protecting the plants, but they are very sensitive to cold. If it is late in the year and it’s getting cold anyway, you should just harvest everything you can and freeze it. You might also try potting up some plants and putting them in the greenhouse, but it must be warm.

Pests: Basil growing in the garden isn’t much bothered by pests, though snails and slugs may eat it when young. Aphids and leafhoppers might show up occasionally too.

Disease: Fusarium wilt can be a problem when it is grown on a larger scale.

Harvesting

When: The leaves are at their best before the flowers appear, though they are still worth gathering even if the plants are actually blooming. It pays to remove any flower stems as they appear, as this encourages more leafy growth.

If done carefully you can get 3, 4 or even 5 harvests from one planting (and make them last for a good part of the summer).

How: Harvest by pinching off the growing tops just above a pair of leaves. You can start doing this when the plants are only 6˝ tall. Always leave plenty of foliage on the bottom of the plant (at least 4 sets of leaves), so it can regenerate and give you another harvest later on.

You can also harvest whole plants, but that only makes sense if you are selling the plants and want to make nice bunches. You will get a lot more leaves by repeated harvest pruning.

Storage: Basil has thin leaves and wilts quickly once cut. It will keep for a few days in a plastic bag in the fridge. You can extend the life of whole plants by keeping them in water like cut flowers.

The easiest way to store basil is to dry it in a warm shady place. This alters its flavor considerably, but it is still very good. It must be dried quickly though, if it takes too long, it will deteriorate and turn black.

It is possible to store the fresh leaves by packing them in a jar and covering with olive oil.

You can freeze the leaves whole in a plastic bag, but a better idea is to put the chopped leaves in ice cube trays and cover them with water. Once they are frozen you can transfer them to a plastic bag.

I usually make pesto (see below) and freeze it in meal-sized portions (so I don’t have to saw up large frozen chunks). You can also put it in a plastic bag (flatten it so that it will break easily when frozen).

Unusual growing ideas

Cuttings: You can root soft cuttings of basil in water and get new plants faster than growing them from seed.

Companion planting: Basil works well with tomatoes. Just plant it all around the tomato bed, to fill in any empty space.

Multi‑plant blocks: Multi‑planting works well with basil. Sow 4 – 5 seeds in a block or cell pack and thin to the best 3 seedlings. These are planted out in a clump and grow together.

Harvest the largest plant when it gets to be a suitable size, leaving the others with more room to grow. When the biggest of the remaining plants gets to a suitable size, harvest it too (you may have to do some judicious pruning to keep both plants growing well). Then harvest the last plant when it reaches a suitable size.

Alternatively you could allow all three plants to grow and just keep harvesting the growing tips.

Container growing: Basil grows well in containers and this is the best way to grow it if you live in a cool climate (this is much easier than trying to coax it along outside).  Put 3 plants in a 12 inch pot and give it a warm, sunny window sill. Be sure to keep it well supplied with water.

You can also try digging up plants at the end of the growing season and bringing them inside (they won’t last indefinitely though).

Micro-greens: Growing basil in this way allows you to have the nice fresh basil flavor in winter. See Micro-greens.

Seed saving: Bees love basil flowers and will cross-pollinate any plants within 150 feet of each other. For this reason you should only have one variety flowering at one time. Basil sets seed very readily; all you have to do is leave it alone. Don’t collect seeds from the first plants to flower (remove them), as you don’t want to select an early bolting strain.

Varieties

If you thought basil was just basil, you are somewhat mistaken, there are actually around 150 types of basil, each with its own unique properties and distinct flavors. The most common include

Sweet: This is the standard basil you were thinking about. I have tried quite a few types of basil, but still come back to these deliciously aromatic, large leaved types:

Genovese

Lettuce Leaved Basil

Superbo

Bush: Sometimes said to be a separate species (O. minimum), It has smaller leaves and is more compact, but tastes like the above.

Cinnamon / Mexican: This has a mixed cinnamon / basil flavor.

Lemon: This has a distinct lemon / basil flavor and is often used for tea. It is popular in Indonesia.

Licorice: This has a hint of anise to go along with the basil flavor

Opal: Has small purple or purple / green variegated leaves.

Purple: Small purple leaves.

Sacred: This is a different species (O. sanctum). It is popular in India.

Thai: Has a lemon / basil flavor. It is popular in Thailand.

Kitchen use

Basil is traditionally used to flavor tomatoes and eggs and is an essential ingredient of Italian cooking. It is probably best known for its use in making pesto (or the French equivalent pistou).

The seeds of basil are not commonly used as food in the west, but they have their own unique properties. They are coated with a substance that swells up into jelly when they get wet (no doubt to provide moisture for germination).

In parts of Asia they are commonly used to thicken and flavor a variety of drinks (nam manglak, falooda). Whether you like these drinks is very much a matter of taste, some find the unusual texture and delicate flavor delightful, and some find the texture to be slimy and revolting.

The seeds work well with cold fruit juices, herb teas and milk to make cooling summer drinks. Go light on the seed (at most 2 tsp per pint), otherwise you may end up eating your drink with a spoon.

Pesto   1 clove garlic 1 cup basil 3 tbsp pine nuts (or almonds or sunflower seeds) ½ tsp salt Pepper ½ cup olive oil 2 oz Romano or Parmesan cheese   Blend the oil and basil together in a food processor, then add the garlic, pine nuts and salt and pepper. It can then be frozen for storage. I think it tastes better if it is cooked for a few minutes, but it isn’t essential. It is traditional to add 2 oz grated Parmesan, or Romano, cheese just before serving (though it isn’t essential).