I am in the process of preparing a raised square foot garden on my 2nd story deck/patio. Could someone with a bit more experience help me to determine if this patio can hold the added weight. Its 4feet wide by 8 long, and the soil depth will be roughly 6-8inches.

also is there an option to post photos here?

 

Yes, if you use a computer, maybe if you use a phone.
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Well, at 32 sq ft that's roughly 20 bags of topsoil, each weighing about 43 lbs. So 860 lbs worth of dirt... dry out of the bag. Each gallon of water adds 8lbs, and soil can hold a lot of water which makes it heavier when it's wet. Safe to say it would be over 1000 lbs once it's built and filled.

Doubt your deck was designed for that kind of constant load... plus people. And we know nothing about your deck structure. Granted, that's equal to 5 normal sized men... which doesn't sound like much, but if you have that PLUS people up there, that's where you might run into trouble.

 

Also, 6-8" really isn't deep enough for a good garden. Things can be kept alive and you can get some production but vegetables need much deeper soil for optimum production.

 

We have a raised "square foot" garden in our back yard with 10" of soil and grow a lot of those veg with no issues. Our soil is all triple mix though. I think 6" is as shallow as you can really go though.

 

The biggest problem with raised gardens on a deck is the ground temperature. Shallow beds get hot faster through and through. The op is asking about a raised bed on a deck... not just a raised bed on the ground.

 

You did not mention sun exposure. What direction does your patio face and is there an overhang above ? How do you handle the drainage aspect ? There are 24 inch deep, and larger, plastic pots. Is this for veggies or flowers/shrubs ? Re-read post #3.

 

The OP has never come back since they posted almost 2 months ago. Don't waste your time to respond.