To grow garlic in raised beds, everything starts with spacing. It is best to allow six inches between cloves to let the roots develop without competing with one another. I learned this the hard way after planting the cloves too closely together, and I ended up with bulbs that were the size of marbles. Cleaning up the airflow is also critical because with plants crowded together trapped moisture can tempt fungal issues.
4-inch spacing
- Bulbs 25% smaller on average
- Higher risk of white rot
- Difficulty weeding between plants
8-inch spacing
- Wasted bed space
- Increased weed colonization
- Reduced yield per square foot
The depth of the soil influences the effectiveness of the spacing. In the cedar beds that are 12 inches deep, I take three parts compost and sand and mix them. This loose mixture allows the roots to explore sideways without being tangled. In beds that are shallow, 8 inches or less, I increase the spacing. Roots are stunted because they hit a barrier.
Overplanting Edges
- Leave 4" (10cm) from bed walls
- Prevents root constriction
- Reduces rodent nibbling
Ignoring Microclimates
- South-facing beds dry faster
- Add 1" spacing in hot zones
- Use shade cloth in heatwaves
Using a homemade grid for spacing is easy, just nail wooden dowels across the frame at 6-inch intervals. You press the dowels into the soil before planting. A client of mine in Arizona achieved a 40% increase in yield using this method, and nice, straight rows lead to very little guesswork, and even fertilizer application.
Read the full article: How to Grow Garlic Successfully in Any Climate
