Tools and Materials
Section off a corner of the garden or yard where a child can do as he or she pleases. Provide high-quality small-scale tools such as trowel, cultivator, rake, and hoe.

Step 1:
Begin by setting aside a section of garden that belongs to the child. It doesn't have to be designed or even particularly attractive, just a place where to explore without risk of damaging your prized plants.

Step 2:
Let the children choose what they'd like to grow. Most often, these will be plants they recognize, such as pumpkins and potatoes. Plants with large seeds, such as beans, sunflowers, and nasturtiums, are easiest for small hands to sow. Though radish seeds are small, children delight in the almost instant growth and harvest. Or plant with a theme, perhaps a 'pizza' garden containing tomatoes and peppers as well as herbs such as basil and oregano.

Step 3:
Children love hiding places. Consider constructing a tepee from tall poles and twine, to be covered with climbing beans and flowers. (Be sure to leave an opening for a door.) Or create a special room: a circle of tall sunflowers with shorter sunflowers or other flowers between them.

Precautionary Tips:
Many culinary herbs are attractive and have interesting scents. Chives, sage, mint, and basil are good choices for a child's garden. Edible flowers, such as nasturtiums, pansies, violets, and calendulas, are also good. Avoid medicinal herbs like St. Johnswort (Hypericum) and valerian (V. officinalis), because they can be toxic if ingested in large quantities.

Since many other plants--even something as familiar as rhubarb leaves--are toxic, teach your child to consult with you before putting anything into his or her mouth. Only a few are so toxic they should not be used around children and pets. Two extremely toxic plants are castor bean (Ricinus communis) and precatory bean or rosary pea (Abrus). Many other plants are toxic in larger quantities and should be avoided in a child's garden. These include angel's trumpet (Brugmansia), delphinium, foxglove (Digitalis), euonymus, morning glory (Ipomoea), lantana, cardinal flower (Lobelia cardinalis), sweet alyssum (Lobularia maritima), and love-in-a-mist (Nigella damascena). Poinsettias are not toxic. A study at Ohio State University established that a 50 pound child would need to consume 50 leaves to experience an upset stomach.

- Planting a Child-friendly Garden
    Courtesy of: National Gardening Editors