Hmm, some thoughts (some are obviously stronger than the others) ...
In exchange for dropping Conjuration (Healing) spells, this druid-varient can ...
Option 1:
spontaneous cast a number of spells/levels as equal to bonus spells for high Wisdom. (ie if he has 0/1/1 bonus slots from Wisdom, he can leave one first and one second level slots open for spontaneous casting).
Option 2:
Offer a bonus feats - pick certain levels and allow a bonus feat at the chosen levels (ie druid level 5, 10, 15, and 20) - i'd highly recommend, however, you do not have a bonus feat at 1st level.
Option 3:
Add skills to the class skill list (ie make Spot or Listen a class skill for this varient)
Option 4:
Increase skill ranks per level to 6+Int mod (rather than 4+Int mod)
Option 5:
Increase hit dice from 8 to 10
Option 6:
Give fast movement like a barbarian in light armor
Option 7:
Make Dispel Magic spells one level lower (ie 2nd rather than 3rd) etc
Option 8:
Change their allowed weapons or proficiencies
Option 9:
Allow 1.5 times the standard maximum HD for animal companions
Option 10:
... hmm, I have to stop myself now.

Like I said, some of the above are, obviously, more powerful than the other ideas before I still listed them to help get the brain juices flowing
I guess it comes down to two questions:
a) how much value do you and your players put on the druid's ability to heal
b) if this druid-varient does not excel at healing, what do they excel at? Diplomacy? Summoning?
Perhaps if you determined this druid-varient's origins, you'll determine the answer. Ie. The ferals are similiar to druids but in fact practice their belief's quit differently. Their divine connection does not allow then the capability to conjure life blood to heal wounds but instead they have learned to ...
(inflict wounds? be more careful in their diplomatic words so as to avoid getting injured in the first place? etc ...)
I'm tired and rambling. I will shut up now
