It is critical to manage the soil's acidity properly to maintain pH at 6.0 or higher. Spinach starts its reproductive stage in response to day length and temperature. As day length approaches 15 hours, seedstalk initiation is accelerated by temperatures of 40 to 50 degrees Fahrenheit. Once initiated, the actual growth and flowering of the seedstalk will be favored by temperatures ranging from 57 to 68 degrees. This factor is what often eliminates one cutting in spring as temperatures grow warmer in June.
Spinach faces challenges from certain weeds including chickweed and lambsquarter.
In fact, spinach and lambsquarter are members of the same family, making chemical control difficult. However, efficient weed-control programs have proven effective. Several insects and diseases, most notably white rust, can cause significant injury to the crop, so vigilant monitoring is crucial. Recommendations for these pests are available in the Commercial Vegetable Recommendation Book available from your county Extension office. Indications are that the demand for high-quality processed spinach will increase as consumers learn about the nutritional and health advantages associated with this leafy vegetable.