Basil is another popular choice for indoor gardening. Not only is basil enjoyed the most when it is freshly harvested and added directly to dishes but basil is also an easy to maintain herb and can be grown without much effort indoors. Basil can be grown in any container as long as the soil is deep enough (as with previous plant, six inches is a good minimum requirement to work with).
Basil is particularly vulnerable to water stress as the roots of the herb will begin to root if there is too much water in the soil. As a result it is especially important to make sure your soil or growing medium has sufficient drainage, such as a coarse soil. Therefore use a container with numerous holes in the base to allow water to escape.
Adding gravel or small stones to the bottom of a container can also help improve drainage. Basil has no special nutritional requirements and can be fertilized using a generic household fertilizer, although it is suggested that you only add fertilizer at half the strength recommended on the label to ensure the soil's pH remains close to neutral. Basil needs at least six hours of sunlight per day, which should easily be found on most windowsills, especially for south-facing windows.
If you do use artificial lighting to replace sunlight you should provide light for a longer period (10-12 hours). This applies not only to basil but all plants you grow indoors. To plant basil, moisten the soil first. Sow the seeds around 0.5cm into the soil with 2.5-5cm of space between each seed, with greater length required if you intend to allow the plant to grow to a larger size.
Basil seeds are particularly small and delicate so if you struggle to position the seeds precisely, you can use the scatter and thinning method outlined in the carrots section; sprinkle seeds generously then remove seedlings after a few weeks to provide enough space. When you sow your basil seeds ensure the soil is not too compact. Dense soil is difficult for the basil seeds to grow in – loose, fluffy soil is required. If your soil is heavy and dense, break it apart manually.
Basil seeds should germinate within 7 days after being planted, providing conditions are right. Once the basil plants have grown between 15-30cm in length you will need to transplant them into different containers or the same container but further apart to ensure there is enough space for all of them to grow. To transplant your basil plants, gently remove them from the soil, using an instrument to loosen and dig around the roots, rather than pulling the stems (which will likely tear the young and fragile plants).
After the basil plants are around 15cm in length, trim the upper stems and leaves using your hands, by pinching a few stalks and leaves away. This helps stimulate upward growth and prevents your basil from growing in a bushy-clumpy formation across the soil surface. To harvest basil simply pinch individual leaves using the same method – you should only need a few basil leaves for a standard recipe.
However you can harvest entire stems, providing you need more basil. Regardless of whether you need basil, you should regularly harvest basil once mature to ensure that the plant is stimulated to keep growing. Ensure that you do not overharvest and remove too many stalks and leaves at once – harvesting no more than 1/3 of the total foliage and stems at any particular time is a good idea (this applies to most plants!).
