Which lens should i use?

[shredboxer]

I have a 18-55mm and a 90-300mm i do a lot of landscape work and trying to find the right one for portraits i need something that is better at zooming and clearer then the 28-55mm but doesnt zoom as close as the 90-300mm and i am sick of having to keep swopping from one to another. any advice??

[RichardTaylor]

Quote
"better at zooming"
End quote.

Do you mean you want a lens that will fill the frame from further away than your 18-55?

If you don't want to swap lenses to cover a whole range of focal lengths, there is really only two solutions.
(1) User a superzoom (18-200mm +) however you may not find the IQ meets your needs.

See this tute (on this site) re super zooms.
Lenses #3 - Superzooms.

(2) Use two bodies.

There isn't really a great landscape/portrait one lens solution for a crop (not full frame camera). However here are to lenses that may meet your needs, especially the first of these two.

Canon EF-S 15-85mm f/3.5-5.6 IS USM Lens Review

Canon EF-S 18-135mm f/3.5-5.6 IS Lens Review