# Plant flowers changing colors. Why? **URL:** \ **Category:** Factual Questions\ **Created:** [May 15, 2005, 3:27pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938 "2005-05-15T15:27:13Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![KRC](https://avatars.discourse-cdn.com/v4/letter/k/45deac/32.png) [@KRC](https://boards.straightdope.com/u/KRC)\ **Post date:** [May 15, 2005, 3:27pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/1 "2005-05-15T15:27:13Z")
I have a rosebush that generally produces lavender colored flowers. I think it’s of the breed called “Angel Face.” Last year it was in bad shape, but after some pruning and plant food it bloomed. This year it also bloomed–but now the flowers are red. What is the explanation for the sudden change in flower color? ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [May 15, 2005, 3:43pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/2 "2005-05-15T15:43:41Z")
I don’t know much about roses, but it may be that the rootstock is outcompeting your budstock: > [@](#): > > We’ve all seen older roses that no longer bloom the correct color. That’s because the root stock has sent up canes of its own variety that compete with the grafted variety on top. The root stock usually wins. In Northern climates, a hard winter can kill the upper grafted variety leaving only the rootstock behind. Because of this, grafted roses often have a limited lifespan. [Own Roots verses Grafts](http://www.uncommonrose.biz/r/grafted.v.ownroot.html) ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [May 15, 2005, 5:09pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/3 "2005-05-15T17:09:34Z")
I believe most rootstock roses are red, too, so that’s probably your problem in a nutshell. Other flowers may change color with the pH of your soil, like hydrangeas. ---
**Author:** ![chefjef](https://avatars.discourse-cdn.com/v4/letter/c/e480ec/32.png) [@chefjef](https://boards.straightdope.com/u/chefjef)\ **Post date:** [May 15, 2005, 11:23pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/4 "2005-05-15T23:23:21Z")
I do think the ph of soil is a factor. I have a friend who’s a landscape architect and he says that’s definitely the case. Would be interesting to transplant a plant from one type of soil to another (with varying ph levels) and see if that changes traits like flower color… ---
**Author:** ![Mr.Goob](https://avatars.discourse-cdn.com/v4/letter/m/c77e96/32.png) [@Mr.Goob](https://boards.straightdope.com/u/Mr.Goob)\ **Post date:** [May 16, 2005, 1:09pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/5 "2005-05-16T13:09:15Z")
I could have wept. My stepmother meant well but one fall she really pruned back all the roses too far. The next year the ones that lived all came up red. Almost all hybreds are grafted onto hearty red root stock. You will see a ball where the graft and the hybred come together. If you lop that off or prune too close to there, only the dominate root stock will grow. ---
**Author:** ![TwoTrouts](https://avatars.discourse-cdn.com/v4/letter/t/a9adbd/32.png) [@TwoTrouts](https://boards.straightdope.com/u/TwoTrouts)\ **Post date:** [May 16, 2005, 1:40pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/6 "2005-05-16T13:40:59Z")
> [@Mr. Goob](#): > > Almost all hybreds are grafted onto hearty red root stock. You will see a ball where the graft and the hybred come together. If you lop that off or prune too close to there, only the dominate root stock will grow. I never knew that! Thank you. Interesting info! I had roses change color like that, but I assuemd the chemistry of the soil had changed. Now I know it was the brutal winter that killed off most of the upper portion! ---
**Author:** ![chefjef](https://avatars.discourse-cdn.com/v4/letter/c/e480ec/32.png) [@chefjef](https://boards.straightdope.com/u/chefjef)\ **Post date:** [May 16, 2005, 10:37pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/7 "2005-05-16T22:37:54Z")
> [@Mr. Goob](#): > > I could have wept. My stepmother meant well but one fall she really pruned back all the roses too far. The next year the ones that lived all came up red. > > Almost all hybreds are grafted onto hearty red root stock. You will see a ball where the graft and the hybred come together. If you lop that off or prune too close to there, only the dominate root stock will grow. Mr. Goob! Good to know - thx for posting. V interesting! ---
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [May 18, 2005, 4:38pm UTC](https://boards.straightdope.com/t/plant-flowers-changing-colors-why/303938/8 "2005-05-18T16:38:19Z")
That’s one reason I like antique roses on their own roots. They’re also mostly fragrant, and many are just about indestructible. Just try killing a good well-established rugosa, especially once it starts suckering!