Left over Rose Feed - will it still be ok to use now?

[NigellasGuest]

Basically it was left in a damp shed, so the cardboard box is floppy and the rose feed inside has clogged together into a hard lump (whereas it should be free-flowing).

Can anyone tell me if it's still all right to use, if I just separate it with a hand fork or something? Or should I just get rid, and buy some more?
Thanks!

[shovetheholly]

I am sure the manufacturers would tell you to buy more... but I've used general purpose feed in this state before without any bad effects! I would just get your psycho on with a pointy bit of metal and break it up, then use!!

[NigellasGuest]

thanks Shove - I have already given some to a container grown rose (hopefully it's the right time of year)?!
I'm not so much worried about ill effects, just potential depletion of benefits. I've got 6 treasured David Austin roses (Gentle Hermione and Port Sunlight - three of each) that are at least five years old now and I want to make sure they get the best nourishment. I guess it's a bit of a false economy not to buy new feed (and remember to store it somewhere dry). It's just that it's a drive to the garden centre and I don't want to buy anything else other than that!