Wheelbarrows ROCK! I should say this more often (although perhaps not at social events - people are surprisingly bored by my wheelbarrow-based small talk). But in terms of children's gardening, they are pretty much the perfect container.
Over the years I have planted various edible gardens in old wheelbarrows with kids. If you choose things like parmex carrots, radishes, tom thumb lettuces and dwarf beans, one barrow can give a child space to grow half a dozen crops. We also created a mobile herb garden from one in 101 Things For Kids To Do Outside which was perfect for housing thyme, chives, marjoram and sage.
And this summer, we made another type of garden - behold the alpine wheelbarrow!
Alpines are great for this sort of of planting because they are generally small and low growing so they won't swamp the space, plus many of them are relatively drought tolerant which means they're happy with the free-draining nature of the barrow.
And of course, being containerised plants, you can work with them all year round so there's nothing to stop you planting up a wheelbarrow in autumn too.
First you'll need a wheelbarrow. You can ask around in case someone has an old one going begging, or try posting up a message on Freecycle.
It'll need drainage holes adding, which is easily done by just knocking through a very large nail every 10-15cm to puncture the base.
Now get the children to give it a good brush out before filling it with potting compost to within 5cm of the top.
Let them place out the alpines until they are happy with the look and then they can carefully take them out of their pots, dig a planting hole with hands or a trowel, place in the plant and firm the compost back around them.
I like to top dress the wheelbarrow with gravel - this keeps the compost from splattering the leaves when you're watering or it rains, and also makes the plants themselves stand out.
We also added some larger stones and various decorations because... well, why not?
In the summer this garden offers a huge advantage because, if you're going away for a few days and you're worried about the barrow during out, you can wheel it into the shade. And all year round its mobile nature means you can position your garden wherever you want, whenever you want, However be warned: it will be heavy so this is best left to grown ups - although obviously under the direction of your head gardener.