Shade plants will die if they are planted somewhere that gets too much sunlight. The harsh afternoon sun and ultraviolet rays will wilt the foliage and disrupt the plant's growth process. A homemade shade cloth can block enough of the light to protect shade plants from the hot midday and afternoon sun. In an ideal world, your backyard would have shady areas for sensitive plants or large shade trees. However, if it doesn't, you can use a plastic tarp to achieve the same results.
Examine the sunlight pattern. Figure out which direction it hits the shade plant. Take into account buildings and other plants that may block it for a period of the day. If the sun comes from the west, for example, you will need to put the tarp on the western side of the plant.
Find out how wide the tarp is, either by reading the packaging or measuring it with a tape measure. Mark two holes on the ground to correspond with the length of the tarp. Make sure the holes are on the correct side of the plant, about 2 feet away, to block the sun from reaching the plant.
Insert the two smaller stakes into the O-shaped rings on each end of the tarp. Pound the stakes into the ground with the rubber mallet.
Insert the stakes deep enough into the ground to hold the tarp in place even when windy. Use twine or cord to attach the stakes to a mesh tarp, if you're using that kind.
Hold each end of the tarp tightly and pull it up and over the shade plants. Determine where you need to place the taller stakes to make a tent-like diagonal shape with the tarp. The angle will not only provide shade cover, but allow the rainwater to run off.
Attach the longer stakes to the O-shaped rings on the tarp. Hammer them into the ground deep enough to hold them there in case of bad weather. The plants should now be covered with the tarp.