Don't dispair it's sounds like the soil!! I'd go along with what greenfingers has said, but add that the garden would also benifit from a good fertilizer. I use 'Growmore' spread liberally and then dig in. Also keep the ground watered in dry weather.
If you're in the UK have a look at these sites and search 'clay soil'. (would be ok in the US to)
www.angliangardener.co.uk
www.rhs.org.uk
www.bbc.co.uk/gardening/basics/
Also do a search for 'plants clay soil' as some plants do better then others in that type of soil.
Good luck and look forward to a 'blooming' spring