You said "when you planted them..." Was that last year or this spring? Are the pink blooms on the same branches as the purple ones were on previously?

Especially if you planted last year, my first thought is that you have branches coming up from the rootstock (many roses are grafted), instead of the part of the rose that's grafted on top of the rootstock. The rootstock on grafted roses is generally something very hardy and is not going to have the same flowers as what you saw blooming previously. Look at the plant -- the graft is usually obvious near the base of the plant -- and see where the branches are coming from. If they're coming from below ground or below the graft, cut them off.

If they're coming from above the graft, I'm stumped, but I'm sure someone who knows more about roses can chime it! Also, if you didn't post this on the rose forum, you might want to, they'll be the experts.

Good luck!

The Neptune I purchased a month ago hasn't been planted yet but is blooming a very dark pink with no signs of lavender. I think it must be the cool weather.

Thanks for your reponses, I did just plant them about a week ago. Hopefully they'll turn purple again..

Thanks!