If you make them out of thick plywood, that will work. You could put 4 small wheels on each too. The expense of wood vs plastic tubs is considerable, not to mention the time in making them. Storing soil might cause the plywood to eventually deteriorate. Lowes plastic tubs (mine cost $4), have lids and are stackable. I'm using mine to make 'earthboxes' and plan on growing veggies in the greenhouse. Lowes has an online website with several different size tubs. Worth a look i think. Just my 2cents - Bob

I use large (5 gallon) buckets, from paint or cat litter or MiracleGro soil that used to come in a bucket. Some of them have snap-on plastic lids. If you can't find freebies, you can buy them at the home stores in the paint dept.

Hi
I use standard 20 gallon garbage cans,available from the box stores around 10 bucks. The square are much better than the round as the will line up nicely without wasting a lot of space. Keeps the materials dry and easy to move around.
I would suggest drilling a few holes in the bottom in case they get wet. gary

I use wheeled plastic garbage cans for bulk storage. I agree with gary, the square ones line up nicely and don't waste space, but I line them with extra heavy plastic bags, to keep the contents perfectly dry.

We also have house cats, so I have all the 5 gal. buckets with lids I could ever use, and then some. They are great for storing smaller quantities of potting soil, etc.

Original poster here:
I guess I thought the plastic option was going to be too expensive. But I found a wheeled storage container that will work. See: http://www.sterilite.com/Category.html?Section=Storage&ProductCategory=35#
I got three of them and they fit under my 8 foot potting table. I think this will work out well. I like it because at a glance I can tell what I am low on. I never buy more than one or two bags at a time so I think it will be plenty of time. THANKS!

The only problem with sterlite is that I found with temperature changes, the plastic cracks.

They don't take freezing well. Rubbermaid products are much more durable.

M