Shade trees are handy in the yard, providing protection from the sun that not only gives relief to you as a person, but also to houses struggling to cool the interior and plants struggling to keep upright. The problem is that trees typically take a long time to grow, and thereby a long time to provide shade. If you are in need of fairly quick heat relief, then try selecting a fast-growing variety that will grow many feet each year.
The royal empress tree grows at a rate of about 10 feet a year and normally gets to a height of about 40 feet. It spreads wide, creating a nice shade, but the limbs can become brittle. The best way to combat potential breakage is to keep the width trimmed in. Leaves turn black with frost, and it produces nearly 20 million seeds a year when mature. The tree needs full sun and can withstand freezing temperatures that allow it to grow in warmer USDA zones down to zone 5.
The tulip poplar offers plenty of shade at a height of between 80 and 120 feet. It isn't really a poplar, but part of the magnolia family. With beautiful blooms from April through June and yellow leaves in the fall, this tree will add a splash of color to the landscape. Tulip poplars prefer soil with a pH between 4.5 and 7.5 that is well-draining and moderately damp. Growth is rapid at about 6 feet a year, and it grows well in the East and Southeast U.S.
Hybrid poplar trees make effective shade trees with wide leaves due to their nice height of between 40 and 60 feet and a width of close to 35 feet. The poplar grows fast, at a rate of 8 or more feet a year, and likes sandy to loamy soil with a pH between 5.5 and 7.5. Plant in a location that is well-draining but stays damp. The hybrid grows well in cooler climates and is planted throughout the Northeast for wood production purposes. However, you can plant them in many areas of the U.S. from hardiness zone 3 through zone 9. Leaves turn yellow in the fall.