One of the biggest challenges a gardener can be faced with is clay soil. A heavier soil, clay has small particles that compact easily, which hinders the movement of air and water through the soil, making it difficult for roots to push their way through. Easily waterlogged, clay soil is quite slippery and dense when wet, while becoming hard baked and difficult to dig when dry. There are, however, some vegetables that will do quite well in clay soils which actually tend to have a much higher nutrient content, often with very few amendments.
Cabbage will grow well in most soils, providing that it is well drained, so amend clay soils with lots of compost before planting. Apply fish emulsion or compost tea about a month after planting to provide extra nutrients. Cabbage likes cooler soils, so clay actually has an advantage here.
Corn prefers deeply dug, well-manured soil, but will tolerate most soil textures. Corn does not do well in cold, wet soils, so be sure to warm soil where corn will be planted with black plastic. Mulch to retain soil moisture.
Both summer and winter squashes will do well in clay soils with lots of compost or rotted manure to aide drainage.. Transplant winter varieties in soil that has been warmed by black plastic and mulch to retain soil moisture.
Pumpkins are not fussy about soil texture, but they do require fertility. Amend with compost when preparing soil, then add a spade full of compost or well rotted manure to each hill during planting.
Okra tolerates clay soils with high nutrients and good drainage. Add compost during soil preparation. Pre-warming the soil with black plastic mulch will speed the germination process. Apply compost tea or fish emulsion once a month.
Swiss chard tolerates clay soils that are rich and well drained. Add lots of compost during soil preparation, but little further amendment is necessary.
Lettuce germinates poorly in warm soils, so cool clay soils may be welcomed. To ensure good germination, prechill seeds in the refrigerator before sowing or start warmer, summer crops from transplants. Raised beds are recommended.
Garlic will do well in well drained, fertile, humusy soil. Raised beds, amended with generous amounts of compost are recommended. Encourage vigorous growth with applications of fish emulsion or compost tea.
Melons do well in well manured, well drained soil that has been thoroughly warmed. Set out transplants into raised beds that have been pre-warmed with black plastic. Give weekly applications of compost tea or fish emulsion.