How to Grow Basil Indoors or Outdoors

Grow basil to have an endless supply of one of the most fragrant and distinctive cooking herbs. This herb is native to Central Africa to Southeast Asia and is a member of the mint family. It is traditionally used in Italian, Mediterranean, Vietnamese and Thai recipes, but there are endless ways to incorporate it in your dishes. Experiment growing and using different types of basil to be able to get the best range of flavors and scents.

It is quite easy to grow basil both indoor and outdoors. But there are some tricks and insights you should know in order to get bushier plants and avoid pests and problems. Basil is an annual herb that can be harvested in very little time (3-4 weeks). It is a great option to grow even for beginner gardeners.

How to Sow Basil Seeds

If you live in an area that has seasons, it is best to sow your basil seeds early in the spring. Those who plan on growing basil indoors do not have to worry about temperatures. You can start to grow basil seeds in seed trays or small pots using peat-free, soil-based compost. Do not put too many seeds since basil has a high germination rate. If you want, put a thin layer of vermiculite on top of the seeds and water lightly. Once they have germinated you can remove the cover, keeping the compost damp.

Thin out the seedlings to give them space and let them grow until they have developed their first true leaves. After you can plant them outside or choose to grow basil in a larger pot. Remember roots will grow and start coming out the drainage holes if the pot is too small. If you grow basil outdoors make sure to see how big that type of basil grows. Smaller types can be planted 10-12 inches apart, while larger types need 16-24 inches.

How to Grow Basil Cuttings

If you already have basil plants and want more or if you are visiting a friend or a neighbor that have plants, you can simply take a cutting that is between 6-8 inches long. Supermarket bought basil won’t probably grow because it is harvested too soon and the rootball is underdeveloped.

Remove the lower leaves of your cutting and place it in a glass of water. Tap water should be left for 24 hours (to let the chlorine evaporate) before putting the cuttings. Place the glass by a window where it can get some indirect sunlight. To avoid bacteria, it is best to change the water every couple of days.

New roots will start growing within a week. When they are about an inch or two long you can transplant the basil cuttings. If you grow basil from cuttings, you will reduce your harvest time by half.

How to Take Care of Basil

Liquid fertilizer is needed sporadically to keep your plants in top condition. You can also include compost or organic fertilizer once per month. Make sure not to over-fertilize basil as it will kill its flavor. Basil grown in pots needs a liquid solution about every 3-4 weeks to add nutrients which are washed away while watering.

Those who choose to grow basil indoors need about six hours of sunlight per day. This plant likes hot weather, so you can also grow it in a greenhouse.

Growing basil outdoors should be done in the early summer, after any frost. Soil and air must be warm if you live in a cold climate. Coolness can stunt or damage the plant, increasing the risk of downy mildew and turning leaves black. You can take your potted plants out during the day (bring them back in during the night) for about two weeks so they get used to the weather. It needs to be at least 50 F (10 C) at night and 70 F (21 C) at day for basil to be permanently outside. Those of us who live in more tropical climates can plant it any time of the year!

grow basil

Choose a sunny spot in the garden to grow basil plants. Make sure to give your plants space if you want them to grow bushy. Those who grow basil outside should be aware plants will die in fall because they will not be able to receive enough sunlight and the cold weather will affect them.

Make sure you grow basil in well-drained soil, with a pH between 5.1–8.5 (acidic to alkaline), since it needs a lot of water to survive. Basil does not like to be wet overnight so you should water it in the mornings and only pour water on the soil, not the leaves. If you plant in a pot make sure to drill holes. Remove all weeds in the soil before planting. Mulching is also a good idea to keep the moisture in the soil.

Basil enhances the flavor of tomatoes and helps prevent insects and disease when planted together. Grow basil next to carrots, peppers, oregano and eggplants since basil takes little nutrients from the soil.

Diseases and Pests that Attack Basil

Those who grow basil may run into some problems with diseases and pests. Beetles (specifically Japanese beetles), slugs and snails are problematic when growing outdoors since they create holes in the leaves. You can hand pick these pests.

Aphids are the biggest pest problem you will have to deal with if you grow basil, especially indoors. Cover plants with a soapy solution by mixing 2 teaspoons dish soap liquid (natural options are preferable since you will be eating your basil leaves) with a full gallon of water. This soapy solution can also treat whitefly and red spider mite.

Powdery mildew is also a huge problem when growing basil. Make sure to provide plenty of space between plants to improve air circulation. Do not water from above (always water the soil) since this can splash fungal spores into the plants. Cut off and discard affected leaves.

Basil can be susceptible to various fungal and bacterial diseases that attack leaves, stems and roots. Black spot, gray mold and Fusarium wilt are common problems. Make sure plants are not overcrowded and soil is warm to avoid these issues.

How to Harvest Basil

It is best to harvest basil regularly to encourage new growth. Leave the larger darker leaves at the bottom of the plant and pick the smaller ones at the top. If you cut the stem just above a set of new leaves, it will create two new branches and so on.

Pinch out flower tips to prevent flowering and make your basil more bushy. Cutting flower buds also helps to maintain the best flavor. Do not worry if flowers appear since they are also edible, but they make leaves more bitter. Bees love basil flowers, so keep them if you want basil honey.

When plants get to about 6 inches make sure to cut off the top 3/4 inch of the plant. This will make them branch out instead of growing tall and thin. The more you harvest basil, the more it will grow. Even if you are not using it you should still harvest your plants with herb scissors. It is recommended to harvest about 20% of the plant at a time. For best flavor you should harvest in the morning since leaves loose moisture throughout the day. Do not wash leaves until you are ready to use them, otherwise they will turn slimy.

Basil does not keep well in the refrigerator, just up to three days, so it is best to harvest when it will be used. If you keep it in the refrigerator it is best to placed basil in a plastic bag and remove all oxygen.

An alternative is to cut stems and leave them in a glass of water until you are ready to use them. Other people chop the leaves and place them in an ice tray with water for up to five months. Basil can also be placed in vinegar or oil to be used for cooking.

Heat steam dissipates the flavor of basil, so it is recommended to be placed on dishes upon serving. The only exception is if you want to extract the flavor in a cream, milk or oil base. For this purpose it is best to warm the mixture gently.