Oh! The Salad Rite of Passage!!!
They're hard but you can beat them.
It's always so much easier to deal with the Salads if you know what the country is like on the west side of Ishad N'ha - you can plan your path to include some narrow bits in the forested areas where Salads can't pass. That gives you a better chance to take them out from a safe distance.
But if you haven't explored this area, you can easily get yourself trapped in a dead end and die die die.
Study the map! I've forgotten exactly where the Salads appear but I believe they show up around the time you get to the burnt out house.
Rough directions to S Castle - go west from Ishad N'ha and follow the path north. Keep to the LEFT - this should take you into some wooded areas. There's going to be one path off to the left in the woods which is a "dead end" literally - so you want to keep to the left but look for an opening to the right (west as you should now be heading south again). Go through that small opening and go south until you get to the moat and head around to the back of the castle.
You may have time, if the Salads get caught in the trees, to off them there OR you may get time to find the back entrance to the castle which requires some swimming. If you can get yourself into the castle - get up on the north wall and wait for the salads and fight, retreat, heal, fight as needed.
The most important things to do: SAVE SAVE SAVE and NEVER lead the Salads back to Ishad N'ha!!
The monsters in the castle are not as bad as the Salads. Few monsters in this whole area are as bad as the salads.
GOOD LUCK!!! And do let us know what happens!!