A backyard flower garden is good way to get kids interested in gardening. However, you will need to make the garden safe for kids, just as you do your yard and house.
If your kids are used to eating vegetables and fruits straight out of the garden, they may not understand that not all plants are safe to eat. While older children will comprehend that they should not eat anything in the garden without permission, curious toddlers need to be supervised to prevent them from munching on poisonous ornamental plants like foxglove, larkspur, and columbine.
Some plants like yarrow and gas plant, are a skin irritant in sunlight. (For a list of potentially harmful perennials, check out http://www.uvm.edu/~pass/perry/oh63harm.html. In addition to supervising kids in the garden, fence off any areas or plants that should be avoided, such as thorn bushes or poison ivy.
Provide child-sized hoes and rakes for your kids to use in the garden. Do not leave pruning shears and other sharp tools within their reach. Always place forks, rakes, and other pointed tools tines down. Use tall stakes for plant supports. Short stakes can cause eye injuries.
When pruning, make sure your kids are out of harm's way. Don't leave pruned stalks at their eye level as the sharp points can do damage.
It's also a good idea to avoid use of all chemicals in the garden, especially in the part that your kids will help plant or tend. If you find it necessary to use them, read the label before applying and don't spray on lawns or weeds when kids and pets are in the area. These chemicals can be absorbed through bare feet. Animals may chew on sprayed weeds or grass.
Store garden chemicals in the original containers in a locked cabinet out of reach of children. Never store them in food containers or soft drink bottles. Better yet, mark the containers with a large skull and crossbones, and make sure your children understand what this symbol means.
When mowing, keep your kids away or turn off the mower when they approach. Look behind you before reversing a riding mower. Young children should never be allowed to drive, or ride on, the mower. Always remove the key from the ignition when the mower is not in use.
Finally, if you let your kids go barefoot, make sure there are no sharp stones or broken glass around. Monitor young children around water gardens. An unsupervised child can drown in seconds in even the smallest amount of water.