This DIY hovercraft
was made by one of the Myth Buster guys back in 2012.
He made it for his kid, but I
was thinking if it would hold a kid it might hold some 5 gallon buckets
loaded with horse manure.
Maybe make it bigger with a
few more leaf blowers and it could be pulled like a wagon across the
swamp and back to the garden.
Keep in mind that the skirt needs to be long enough give enough float height and conform to the contours of the ground. Loose too much air and you're stuck.
Looking at the racing videos on youtube, driving one looks like a lot more fun than pulling one, though.
With all the air being pumped through, you'd expect a lot of spray around the skirt when you're crossing water or mud. But on the video's I've seen it doesn't seem too bad.