In a container, the roots are stuck in a small space and quickly mine it free of any nutrients, especially if you were going easy on the nutrients to begin with.. The oils in herbs make them special. The plant still needs some food to grow, and when that food runs out you will need to fertalize.
But what if you need your basil.it does not like water on its leaves.
If you love fresh spaghetti sauce or pesto, than you've just got to have fresh basil and other herbs all year round! Sure, a nice 1 X 4 window garden getting at least 4 or 5 hours of direct light from a sunny window will give you something to pinch here and there. Basil would take well to the bright conditions under a metal halide, as it is a Mediterranean, sun loving herb. This is usually about 4 to 6 weeks, depending on the herbs.and lots of it? Basil and cilantro need just a bit more light, and really prefer 8 hours or more of direct light each day.
If you feel the top of the soil and it is dry, than you need to water. Very fast growing herbs often grow plain leaves and stems more quickly than they can produce tasty essential oils.
If you really want to keep your plants healthy, I also recommend 10 ml/gallon Thrive Alive B1 and Maxicrop liquid seaweed in every drop of water you give to your plants.
The goal is a vegatative light cycle (18 hours on), with eight or more direct sun or bright artificial light. You need to have containers with holes in the bottom, and you need to add an inch or so of perlite or gravel to the bottom of each container as you transplant. In addition to this if you want fresh pesto, just a pinch here and there is not going to cut it. Whenever the light levels are low, give them a boost.
To keep initial growth rates in control, I use a soil mix with just enough nutrients. Your herbs like their soil to drain fast. What these people really mean is "don't grow your basil too fast" (sorry to pick on basil). Here's what you can do about it. You can grow enough basil for a few servings of pesto now and then, and Emergency Light still have enough always at your fingertips.
Or, with a small metal halide light you would have a larger area with better lighting.
When the herbs have been in any container for ten days or more, you need to begin feeding them. You could surely produce an abundance of any herbs you choose for your culinary and aromatic delights. It is best to water thoroughly, but less often.
It has been said that some herbs grow better, or should be grown in, poor soil..
Feed with half strength nutrient such as Maxsea 16-16-16 every two weeks. You will get your highest essetial oil levels when you harvest at the end of the dark period, assuming you do not leave the lights on 24 hours a day..
As soon as the herbs have grown enough leaves to be pinched without affecting their growth, you can begin using some of the herbs. Gardens with mint, rosemary, bay leaf, savory, oregano, chervil, sand thyme are some of the easiest to grow this way. Mix 2 parts sphagnum peat to 1 part perlite, and than add 20 percent worm castings. Often you will hear "basil grows better in poor soil" or "your basil will taste better if you don't fertalize". Use this mix whenever you transplant. Adjust the Ph of any mix using sphagnum peat moss by adding 2 teaspoons of hydrated lime for every gallon Led High Bay Light of soil mix. Finally, water basil from around the base. However, as you will see in the next two sections, this is all taken into consideration together with the growth habbits of your herbs. Herbs like basil are best when harvested before flowers open. or You can substitute peat with coconut coir or vermiculite, which do not need Ph adjusting. This will help with essetial oil production.
When growing in a container, it is a little different.. Finally, I add 1 tablespoon of kelp meal for each gallon of soil to add plant hormones and to give beneficial micro-orgnisms something to feed on. The B1 is vitamins and root hormones, and the seaweed is trace nutrients and plant growth hormones. Water the container until some water comes out the bottom. Another way is to pick up the container and check how heavy it is. Two or three fluorescent lights above your plants will greatly increase their growth and yield.