Not sure what zone rating Ohio gets, but I'm pretty sure both cucumbers and cantaloupes are hot climate crops. If no one else from your zone replies, you'll have to look up your local extension sources. Here in Texas, we have a longer growing season and I plant my container cucumbers in March-April and cantaloupes a little later and also in the summer.

I sow all the vegetables you mentioned direct (I don't grow zucchini). In your zone, you may want to sow yours indoors and then transplant the seedlings when the last frost is over.

You can search first and last frost and average temperatures online for your zone. Important information to know and have handy.

Search for the dates of first and last freeze in your zone (and relevant average monthly or seasonal temperatures) would be better.

I am planning on my first container garden as well. I have a small but very sunny concrete backyard. Eastern PA

I am looking to do the Italian basics I know from childhood. Tomato Zucchini Eggplant Peppers.

How early do I neeed to have them in? I was planning on using 10gal spackle buckets will this work?

Don't put any of those out until the average nighttime temperature is above 55 F or they will get stunted and possibly never fully grow. I also have a small concrete backyard with some sun and for any of those plants 5 gallons or larger should suffice per plant, or smaller for dwarf and patio varieties.

Cynthia, I too wonder about the effect of frost and temperature on containers that are above the soil line. It probbaly depends on the size of your containers and even the color of them (black will absorb more sunlight and stay warm, but may get too hot in summer).

so ONLY one plant per 5gal bucket? (i meant 5 not 10 in OP)

Here is what I think I have learned from rooting around here... soiless mix, sceen and drainage holes at bottom. shade the container so as not to burn roots. water in the morning.

anything else I am missing? Would I be better served to buy some earthboxes? Budget is an issue.

I am planning on buying the seedlings from a local urban farm because the house is under construction and there is no room for growing from seed this year.

I'd encourage you to make the boxes yourself. Cheaper and more satisfying than buying them.

Follow the planting guide that is on the official Earthbox site. It's also one of the links in my little how-guide at my Flickr photoset.

Here is a link that might be useful: rooftop EBs