When you purchase a plant at your local hardware store or garden center, check to see if it comes with a plant tag attached to a leaf or a plastic stake wedged in the soil; this plant label will inform you of the plant’s light requirements. It will specify how many hours of direct sunlight the plant needs and describe the recommended light conditions and growing conditions for the specific plant species.
There are five types of sunlight a plant may require.
1. Full sun
Many plant species can endure—and even thrive under—a full day of sunlight. Grow sun-loving plants away from foliage, fences, or buildings that cast long shadows for most of the day. Full sun plants don’t necessarily need all-day sunlight, but they generally need at least six hours. Afternoon sun tends to be stronger than morning sun, so if you know you can only offer a plant six hours of sun exposure, plant it in a spot that gets most of its sunlight in the afternoon. Full sun perennials and drought-tolerant plants like succulents and salvia love full sun, as do most plants you’d grow in a vegetable garden. Reserve sunny spots for these species.
Most of the annual vegetables do best in full sun, i.e., squash & tomato – especially morning sun, cucumbers (well drained soil/fertilized soil, eggplant, peppers (water daily)
2. Partial sun
Partial sun plants typically also need around six hours of sunlight (and no less than four), but they also benefit from some time spent in the shade. Morning may be the best time of day for these plants to receive their daily dose of sun. Hot afternoons may prove overwhelming for part sun plants, so give them several hours of direct sun in the morning, but keep them shaded from the most intense afternoon heat. Many flowering plants do best in partial sun.
- Bean and squash family. Bush beans and summer squash are in season during the summer but will thrive in areas with less sun.
- Broccoli & cauliflower. Partial sun encourages tighter heads and slower development of flowers; plant in early spring or autum
- Too much sun will dry out broad leaf cabbage
- Carrots: too much sun produces more foliage than root
- Leeks & onions: less sun encourages more root growth
- Root vegetables. Potatoes, beets, radishes and carrots will bloom in partially shaded areas.
- Vegetables from the bean and squash family. Bush beans and summer squash are in season during the summer but will thrive in areas with less sun.
- Adapted varieties of bush tomatoes. Some bush tomato varieties are adopted to cool regions and can thrive in shaded plots. They usually come with regional names on labels such as Oregon, San Francisco, and Siberia.
- Partial shade: If a plant tag calls for partial shade, take care not to overwhelm the plant with sun. Plants that thrive in partial shade typically need less than four hours of direct sunlight, but more than an hour and a half. Partial shade plants do well when planted in an east-facing yard or garden bed. They’ll still get enough sun during the morning hours, but they’ll spend afternoons in the shade.
- Cool-season vegetables. Asparagus, brussels sprouts, swiss chard, radishes, and parsnips bloom in shady spots. Shaded conditions will extend the growing season of your cool-season crops.
- Leafy vegetables. Leafy greens such as lettuce, cabbage, and watercress are good in the shade. And so are dark green vegetables such as spinach, collard greens, and kale. These green edibles will even lose a bitter taste if grown in a shaded garden.
4. Dappled sun
Not many plants require dappled sunlight or dappled shade, but this care description indicates that they need less sun and even more protection than part shade plants. Plant a dappled sun or dappled shade plant under a tree, where the sun filters through the tree’s leaves in a “dappled” pattern. Morning and early afternoon sun are fine for these plants but limit them to just a little sun per day.
- Leafy and root crops: Leaf lettuces love less sun; too much sun creates a bitter taste; mustard greens, spinach, swiss chard
5. Full shade
Full shade plants still need sunlight (all plants do), but they can get by with at most three hours of direct sun per day. In nature, these plants live in shaded areas like the forest floor. You can grow full shade plants in the shadiest parts of your yard, or you can grow them indoors and keep them as a houseplant. Full shade plants are low maintenance once established.
- Endive: the most shade loving of the lettuce plants; but harvest before first frost. Kale loves cold weather and less light & plenty of organic matter in the soil.