Just had a similar problem today, OH for the FIRST time decided to dig a bed :o :o I think he is having a mid life crisis or summit, but the ground was dry as a bone....so....... we bought some compost and have dug that in cos we have nought else.....time will tell!
I plan to put everything I can get my hands on into it, homemade compost, manure, and all that good stuff, anything that will enrich the soil really.