I often use garlic in my recipes as it is such a distinctive tasting herb that brightens up many dishes. It is very simple to grow at home even if you do not have much space in your garden. You can plant either directly into the soil or into pots if you wish to save space.
There are many different varieties of garlic that you could select, but ensure you select a cultivated variety which is suitable for colder climates. This is because you should plant garlic in pots in mid-October as the cold weather helps to produce garlic with larger bulbs and more cloves. Do not plant supermarket bought garlic as they would have been treated with a chemical to prevent sprouting and will not tolerate cold conditions. If you wish to plant as late as April you can, but the garlic will be smaller. However you could use supermarket cloves at this time of year as it is warmer, just ensure you wash the cloves thoroughly before use.
Select a suitable container and fill it with John Innes ‘Seed and potting’ compost. Separate the bulb into single cloves and select the bigger, stronger cloves. The individual cloves should be planted 15 cm apart, or place a single clove in each pot. Plant in an upright position, tip pointing upwards, in a hole 3 cm below the soil. Water thoroughly and place the container in a sunny position. Feed the containers in the summer with general purpose plant food every two weeks.
The garlic is ready for harvesting around August/September depending on variety type. You need to lift them when they are ripe, as lifting too early will mean the bulbs are too small, and lifting them too late will diminish their taste. They are likely to be ready when the leaves start to turn brown. You can check if they are ready to harvest by removing a bulb and peeling off the papery layers surrounding the bulb; if you can remove three layers than it is ready to harvest, but if you can remove more than they are not ready so leave them for a few weeks. When lifting garlic, gently remove the bulb with a trowel to prevent bruising. To store garlic bulbs successfully, wash and dry the bulbs and place in warm area to dry out. Once dried they can be stored for 3-4 months.
Source : http://seedtofeedme.blogspot.com/2011/04/growing-garlic-in-containers.html