Cucumbers can provide ground cover for trellised peas, and both plants will aerate the soil for each other. Plant them together in rich, loamy soil and full sun.
Corn provides a ready-made trellis for peas, and both plants will benefit from sharing nitrogen-rich soil.
Planting peas with potatoes can maximize space. Sow peas into the trench next to hilled potato plants for a water efficient planting.
Cilantro and parsley support beneficial insects that will prey on pea pests. They'll grow well in peas' shade, and in turn they'll shade the soil for peas in the spring.
Marigolds and nasturtiums deter most garden pests, including aphids, nematodes, and whitefly. They'll also attract pollinators and beneficial insects and shade the soil for peas.
for 3 more companion planting ideas + what not to plant with peas