Typically, I advise against planting garlic in the greenhouse unless you have a love of garlic and have extra room in your space. Yet, somehow I found myself planting it anyway!
A recent trip to the refrigerator yielded two garlic cloves that started to sprout in the little bin at the top of the door. I pulled off the two cloves and off the greenhouse I went.
Garlic is easy. Just stick the clove into the soil pointed end up, cover with soil and away you grow. Garlic can handle light frost during the winter. Make sure to remove the flower buds as they crop up so more energy is diverted into growing a larger bulb.
Classification: Annual in areas of hard frost.
Sow: Spring or Fall. Fall sowing will typically yield larger bulbs in an unheated greenhouse.
Sowing Depth: 1 inch
Height: 1-3 feet
Water: Allow soil to dry between watering.
Time to Maturity: 90 days
The keys to success are a lot of sun and rich, well-drained soil.