Garlic is a flowering bulb that requires plenty of nutrients to grow and form good cloves. In the soil, you provide those nutrients with lots of aged manure, rotted leaves or a balanced organic fertilizer. For plants in a glass of water, the bulb itself will provide the nutrition. In hydroponic systems, you either use the commercial solutions available or a solution of organic fertilizers and water.
Hydroponics, or hydroculture, offers a way to grow plants without soil. The garlic cloves are placed in a rack or suspended in inert mediums like perlite or gravel. Below the racks or medium is a nutrient solution into which the plant roots grow. Hydroponic systems can be set up in a greenhouse or – with the proper kind of lighting – any indoor room.
Systems and Nutrients
A number of commercial hydroponic systems are available and there are also instructions to build your own. You can also create your own nutrient solutions with the following organic materials (be warned, they may clog systems):
- Blood, hoof, horn or fish meal
- Ashes from bones
- Powdered kelp, seaweed and minerals
- Animal and poultry manures
The Odor Issue
One disadvantage of growing garlic in a hydroponic system is the distinct odor of the plants. If you grow in a greenhouse or garage, that might not be a major problem, but in other indoor locations, the odor can be significant. If your only option is something like a spare bedroom, be prepared to open windows frequently or use other means to combat the smell of the garlic plants.
Garlic on the Windowsill
A clove of garlic placed in water will sprout. This method is similar to the practice of forcing flowering bulbs (which is what garlic is) indoors. Small glasses like shot glasses work well. Put enough water in the glass to come halfway up the side of the clove. Change water daily. Place in a sunny windowsill and harvest when green shoots are several inches tall. Discard cloves after harvest.
Growing Garlic Hydroponically
Most garlic (hardneck especially) grows better if exposed to cold temperatures prior to sprout. Vernalize your cloves in a refrigerator for six to eight weeks. Plant just below the surface of the hydroponic medium with pointed ends up. Space cloves four inches apart. Garlic will grow best with 10 to 12 hours of light; don’t leave lights on 24 hours a day. Harvest cloves when they reach the desired size.