If you have a small outdoor space to work with but still want to enjoy some small-scale gardening or flower beds, flower boxes allow you to easily plant flowers, herbs and even lettuces or tomatoes. There are many do-it-yourself flower box plans available, ranging from the simplest flower boxes to the more complex and larger flower boxes. You can make a simple, attractive and inexpensive flower box in a half day's time, using 2-by-4 inch lumber. For your work, you'll be rewarded with a lovely homemade flower box.
Cut four pieces of the 2-by-4 inch boards to 17 ½ inches long. Cut each end at opposite 45-degree angles to make a mitered cap for the flower box.
Cut 14 pieces of the 2-by-4 inch boards to 14 ½ inches long. You'll use these pieces for the four sides of your flower box.
Cut five pieces of the 2-by-4 inch boards to 10 ½ inches long for the bottom of the flower box. Place the cut pieces of lumber into three separate piles, one pile for the top pieces, one for the sides and one for the bottom.
Build the two front and two side walls of your flower box. For the front walls, place four of the 14 ½-inch-long pieces side by side lengthwise. From the top of the first piece of wood, hammer a nail into the next piece by driving the nail at an angle. Repeat on the bottom. Make sure to keep the assembly flat and square.
Build the two sides using three of the 14 ½-inch pieces each in the same manner as you did in Step 4.
Nail the front and side walls together, with the side walls flush and inside of the front walls. Note that only the four boards will show on the width of the front pieces and the edges of the sides will not be visible.
Make the floor of the planter by nailing three of the 10 ½-inch long pieces side by side across the other two 10 ½-inch pieces set perpendicularly, which act as runners and keep the bottom of the flower box raised off the ground. The two bottom pieces (runners) should protrude about ¾ of an inch below the walls, which will allow you to secure them by nailing them to the base of the front and side walls.
Nail the four 17 ½-inch pieces cut at a 45-degree angle to the top of the front and side walls to form the capping.
Stain or paint your flower box to protect it from the elements, but be sure to use plant-friendly products.