If you have loamy soil, you're in luck. This type of soil is preferred by vegetables as it is well-draining and, more often than not, richer in available nutrients than other soil types. Loamy soil is so preferable that gardeners without it amend their soils to get it.
Why Loamy Soil?
Soil is made up of particles that vary greatly in size, giving each type of soil its distinctive makeup. The three major particle types are sand, silt and clay. This is why different regions have sandy, silty or clayey soils.
Sand particles are larger, grainy and course, allowing water to drain right through. Clay particles are small but heavy and hold water. Silt is in between the two.
A loamy soil has all three particle types in balance with each other. It holds moisture enough to keep plant roots moist while draining well enough to prevent roots from becoming waterlogged.
Loamy soil may be preferred but isn't always necessarily ideal. Other factors also come into play when planning a garden, including available nutrients, temperatures, exposures and more. Adding rich compost can improve even loamy soils.
Summer vegetables, also known as warm-season crops, grow best under the hot sun of summer. These crops tend to be tender and sensitive to cold and frost.
Tomatoes (Solanum lycopersicum), eggplant (Solanum melongena), peppers (Capsicum spp.), pumpkins (Cucurbita pepo), cucumbers (Cucumis sativus) and cantaloupe (Cucumis melo var. cantalupensis) are examples of tender and very tender crops that do well in well-drained, fertile, loamy soil. Cucumbers, pumpkins, cantaloupes and many of their relatives thrive in warm soil; you must wait until the soil reaches over 70 degrees Fahrenheit. These three, in particular, are also heavy feeders.
These crops germinate best when soil temperatures are between 80 and 95 degrees Fahrenheit. Some, including cantaloupe and eggplant, may become stunted when daytime temperatures stay at or below 55 degrees for a week.
Although a warm-season crop, sweet potatoes (Ipomoea batatas) grow best in sandier loam soils that isn't too rich.
Although summer vegetables take center stage, a large variety of crops do better in cooler temperatures. These are known as cool-season crops.
Cool-season crops include most of the root and leafy crops -- most of which also prefer a rich, loamy soil. Some are considered semihardy, meaning they prefer cooler temperatures and can handle light frost. Others are hardy and thrive in -- believe it or not -- late fall, winter and early spring.
Semihardy crops tolerate light frosts which typically occur when the temperature hits between 29 and 32 degrees Fahrenheit.
Root crops in this category include carrots (Daucus carota subsp. sativus), which thrive in loose, deep loamy soil free of stones; beets (Beta vulgaris), which thrive in loamy soil high in organic matter; and rutabaga (Brassica napobrassica), which will grow in almost any soil but produces best when moisture-rich loamy soil is the growing medium.
Leafy crops that are semihardy include lettuces (Lactuca sativum), raddichio (Cichorium intybus var. foliosum) and Swiss chard (Beta vulgaris sups. vulgaris).
Lettuces and raddichio are shallow-rooted and prefer consistently moist -- not wet -- soil.
Hardy vegetables are those that can't take the heat -- they need the coolness of fall, winter and early spring for overall health and to produce the best flavor. Several cole crops -- many varieties of the mustard family -- take center stage here. According to University of New Hampshire Cooperative Extension, cole crops do best in well-drained loams.
Cole crops include kale (Brassica oleracea var. sabellica), broccoli (Brassica oleracea var. italica), brussels sprouts (Brassica oleracea var. gemmifera) and collards (Brassica oleracea var. acephala).
Some of these, particularly kale, have a better taste when hit with hard frost or even snow.
Other hardy vegetables include radish (Raphanus sativus), spinach (Spinacia oleracea) and turnip (Brassica rapa subsp. rapa).
Turnips can also handle poor, sandy soils.
Understanding Plant Requirements
Most vegetables will list "moist, well-drained soil" on their plant tags. This is a vague term, but it does hold value. The term means your soil needs to allow water to drain through quick enough that it doesn't form standing water or hold water on the roots. It should also have particles and a texture capable of holding moisture without pooling. All these vegetables do best in moist, well-drained soil, making loamy soil the ideal growing medium.