So you have a shady spot in your yard that you're not sure what to do with. The first step is determining the source of the shade. If your garden shade is due to tall, mature shade trees or evergreens, you'll want to plant smaller, ornamental trees, such as serviceberry or dogwood, that won't compete with the larger trees' size. If your shade is due to a wall or the side of a building, you have a few more options and can plant trees that will eventually grow taller than the surrounding structures.
Test your soil. Scoop samples of soil from several areas in your yard into the vials or envelopes provided with your soil test kit. Mail the kit to your local county extension office. You'll receive a soil analysis report in a few weeks detailing the composition of your soil (clay, sand or a mixture), nutrient deficiencies and the pH level. Follow the extension office's recommendations for improving the soil, which usually includes tilling in compost or manure and possibly lime.
Check with your local county extension office for shade-tolerant trees that grow well in your area. Note how much water your garden area receives. Depending on your climate, your shade garden may stay fairly moist or be quite dry. Select tree varieties that naturally thrive with the soil type and moisture level you have.
Select a site location at least 20 feet away from mature shade trees and 10 feet away from buildings or walls. Plant trees well away from any power lines and consider how the tree will fit in your landscape when mature.
Water trees weekly, especially when the trees are young, if you have dry shade. Plants and trees in shade gardens require less water than those in full sun, but they still need moisture. If your shade is the result of large trees, the smaller trees underneath may receive little moisture from rainfall. Test the moisture level by putting your finger in the soil. It should feel moist 2 to 3 inches under the soil.
Fertilize sparingly. Most trees need little fertilizer, especially if you amended the soil before you planted the trees. Fertilize in early spring by applying 2 lb. of granular fertilizer (10-10-10) for every inch of the tree's diameter. Keep in mind that a mature tree's root spread is at least as wide as the canopy, so apply fertilizer in a wide circle around the tree. Activate the fertilizer by watering it for 15 minutes.