I don't have the specialized knowledge you need, since I am in zone 3 :)
But I do grow both of them in pots and have some general observations.

Betty White -
Plus - Lots of very fragrant flowers. Huge pinky/white. One of my very favorite roses. It is very bushy and showy.
Minus - Every time it rains, the blooms turn brownish. It rains a lot here - so it's frustrating.

A Shropshire Lad
Plus - Beautiful soft pink blooms that have a lovely spiral.
Minus - grows taller and is not very bushy. Smells faintly of cucumbers. Blooms hang a little bit.

Someone else will give you more pertinent info for your zone - but maybe this will help a little. :)
Carol

Andrea, Shropshire Lad is an excellent choice for your situation in my opinion. As for the composition, definitely go with terra cotta. I'll give you a few tips on the soil composition too. I generally do 3 parts potting soil, 3 parts soil from your garden or the woods (for the beneficial bacteria and mycorrhiza), 3 parts sphagnum peat moss, 1 part compost, 1 part river silt. Also throw in some campfire ashes, kelp, bonemeal, blood meal, and some Ironite PLUS, if you can find all of those things that is. Good luck.
-Andrew B

I would strongly recommend Lady Emma Hamilton. I grow mine in a large terracotta pot and it forms a nice shrub. It has over 40 buds on it now for its second flush and the scent is outstanding. It also has pink tones not captured in David Austin photos. Shropshire Lad is gorgeous though.

I use E.B. Stone potting soil with micorrhizae, E.B. Stone plantng compost, bone meal, blood meal, and perlite. My potted roses love it.

This post was edited by racin_rose on Wed, Jul 31, 13 at 20:32

LEH

This post was edited by racin_rose on Wed, Jul 31, 13 at 20:31

I have both A Shropshire Lad and Lady Emma, and if you're looking more for a bush-type, I'd like to suggest Lady Emma, as she seems like a smaller and more compact plant. I also LOVE her, she smells so good!

Currently, I have A Shropshire Lad in my pot ghetto because I had to dig him up in order to do some landscaping. ASL has suddenly perked up and has set lots of new buds and growth. Here's a whole bush shot - looks a bit lanky, which might not be what you're looking for. I'm in California and have been told that ASL will probably get big in this climate.

Thanks for all your answers.

Guess I'll have to look at Betty some more. I really want a bushy plant that will have blooms on all sides. And I definitely don't want a cucumber smell!

I have used the E.B. Stone products and like them a lot. And a terra cotta planter is definitely the most attractive. So that's a wonderful suggestion.

I haven't seen anything on Lady Emma but will do more research. Maybe this is the rose I want.

Thanks again,

andrea

Shropshire Lad is graceful and beautiful, but might not be right for your pot. The branches arch and spread. Mine takes up a lot of space. I find the rebloom to be poor. Betty White has lovely blooms and good rebloom. It's fine if you don't mind a stiffly upright rose with rather large canes.

Rose, sounds like neither of them would be what I want. So I have posted a general question about Carding Mill. Maybe that one will be right for me.

Thanks again,

andrea

I have loved the photos I have seen of Shropshire Lad for a long time but have hesitated to get it because I heard it was a bit of a shy bloomer. Is the the case with those of you who grow it?