Building Raised Beds
There are several reasons to use a raised bed. With a raised bed you can create the right soil mixture. This is especially helpful when the soil around your house isn't ideal. Also, by raising the soil in a wooden frame above the surface of the ground, it will actually warm up sooner in the spring. Seeds tend to germinate faster and roots will be stimulated to grow. In the fall, you can cover the bed when temperatures drop and extend the growing season a little longer.
I have 2 sets of square beds. One set contains four 4' x 4' square beds and the other, four 6' x 6' square beds. The size bed you choose depends on your site and design. Just remember to create beds that are a manageable size. You should be able to reach into the middle of the bed without stepping on the soil.
Simply cut the ends of the boards at 45-degree angles and attach them together to create a square using 3 wood screws to hold together each corner. Put a level along the top of the board on each side to make sure the frame is balanced. You may need to dig a small trench under the frame so it sits level on the ground.
Position the 2" x 2' stakes every couple of feet along the inside of the boards and hammer them into the ground about 1'. This will help anchor the beds. With the frame in place, you are ready to add the soil.
Since I have heavy clay soil in my garden, I create a blend of 1/2 garden soil, 1/4 well rotted manure and 1/4 compost or humus. Depending on your garden's soil, you may want to create your own mixture, but what you're going for is a healthy, disease free, blend of soil that has plenty of organic matter and drains well. Just remember, its always a good idea to wash fruits and vegetables that you have grown at home even if you don't use chemicals or pesticides due to the fact that soil may be on the plants.
Your soil mixture should come up to about 2 inches from the top of the board, just enough room for a layer of mulch so you can tuck your plants in. You can order soil, manure, and compost to be delivered by the cubic yard or for smaller beds you can use bagged material. A cubic yard covers about 100 square feet 3" deep.
To make watering easier put down soaker hoses and many brands are made from recycled tires. Just snake the hoses about eighteen to twenty inches apart through the bed. These hoses actually sweat water and will keep the soil moist and keep the foliage of your plants dry.
An additional option is to top your soil with a weed barrier or filter fabric. It's a nylon based product and it's great because it lets the air and water in and keeps the weeds out. Just unroll it across the raised beds and make sure there's plenty of overlap so there's no chance of a gap occurring over the season. When you set out your plants, just cut the fabric with a sharp knife in an X and insert the plants into the soil through the opening and for seeds, I just make a long split and plant the seeds along the cut.
The last tip is to add an organic mulch. This will keep the roots cool and the weed barrier in place.