If the pH is too high, leaves may have a yellow color referred to as chlorosis. Fertilizers - Spinach requires a high level of fertility, especially nitrogen. Early spring spinach may require larger quantities of fertilizer than fall crops. Fertilizer is often broadcast and worked into the soil prior to seeding. Boron deficient spinach has dark roots and numerous small, flattened, yellow leaves and is generally stunted.
Older seed is even less viable and germinates more slowly and irregularly.
It is important to use new, fresh seed each year. Multiple rows on a bed will increase production efficiency per unit of land. Beds can range from 3 to 5 ft wide depending on planting and cultivating equipment. Raised beds offer many advantages for spinach production. This spacing will require 10 to 20 lb of seed per acre.