When plants begin to flower, they need an inch per week regardless of soil. Expect peas to be ready for picking about three weeks after the plants begin to flower. They will be if your site has been cultivated before. But if yours is a brand-new garden, before you plant your seeds, you'll need to coat them with a powder called an inoculant. You'll find inoculants, and instructions for using them, at nurseries and in seed catalogs.
Peas come in a multitude of varieties.
Explore seed catalogs and garden books to find the best choices for your climate. Pea vines are delicate and break easily. Once they've grown up, don't poke about in their vicinity any more than you have to until harvest time. Peas can fall victim to several diseases, including powdery mildew, fusarium wilt and root rot. Fend them off by choosing disease-resistant varieties, timing your plantings to coincide with cool weather, and rotating crops.