Vigorous Root Systems

I started many of my seedlings in clear plastic cups and this has allowed me to really get a great view of the root systems of my various seedlings. As I repot the seedlings into larger homes, I can confirm what I’ve seen through the cups. It seems to me like there are some varieties which yield seedlings with vigorous root systems fairly consistently. One of those, for me, has been Westerland.

I prefer growing roses as own-root and of course the arguement for the other is that rootstock can be more vigorous than the grafted rose. I’ve heard people discussing foliage, cold hardiness, disease resistance, floriforousness, etc., but I haven’t seen discussion on trying to develop roses which are vigorous as own-roots.

Any thoughts on this? Any cultivars that, in your experience, do tend to consistently have seedlings with vigorous roots?

Alicia

It is my opinion that he larger shrubs or landscape roses will more and mare be grown ownroot. If only because getting rid of the rootstock suckers is not readily to consider for public plantings.

I know from personnal communication from leading breeders that selection for VRS has been volontarly forgotten for a long period where grafting was considered as favoring breeder’s rights. It is no longer now as landscape roses are finding a large and expanding market.

It is with desease resistance and plant architecture among my goals for close to species crosses.

VRS you can find in many species such as bracteata, roxburghii, helenae, banksiae to name a few with particularly impressive large divided roots set growing strong downright. VRS provides them and many hybrids superior strength and drough resistance

The suckering species like gallica, nitida or rugosa do not have such VRS. Neiter do most moderns cvs.

Pierre Rutten

Alicia:

That is a good question. You are right that the root system should be considered. Though rooting ability is a different trait than a vigorous root system, Mr. Ralph Moore has continued to work hard in that direction. I would think that there is probably some correlation between ease of rooting and vigorous root system, though the traits may not be linked. Minis have been breed to a large extent for their ability to root easily.

Jim Sproul

There is also something root-wise that I’ve seen for the past two years in our rose gardens: a tendency on the part of several species roses to ??root graft almost too readily to other plants (in our case poke weed and privet hedge treated with Tordon.)

The abstract in the Rose Production Symposium this past summer that talked about root graft transmission of RMVs lead to my looking more closely at some roses that had minor tordon damage when weeds were treated within four feet of them.

The most recent example is R. laxa damaged when both Dortmund and Helen Bland were undamaged although the weeds treated were growing up in the midst of their canes, three to five feet from laxa.

I’ve also seen damage in R. roxburghii and Mrs. F.L. Skinner and Pink Masquerade.

This potential root-to-root sharing could make for healthier plants, but could also lead to sharing of serious problems.

There are articles on root branching and flexibility and the best architecture for commercial rootstocks. I suppose that is for mainly harvest and handling. Dr. Buck has an article on his IT rose rootstocks and discusses this. I don’t know how much this applies, but perhaps for own-root roses a similar architecture may be useful for commercial harvesting and handling purposes. Perhaps a well-branched root system with flexible roots may also correspond with vigor, or at least less damage during harvest and handling.

Sincerely,

David

David,

Those are interesting points I hadn’t thought of, that vigorous may have different aspects: flexibility, well-branched, etc.

My own interest is just in a root system which grows strongly and is able to support the plant well, since I have no plans to harvest or transplant mine. This year I have a large crop of seedlings (OP) from many cultivars. It will be interesting to see if some do markedly better than others out in the garden by the season’s end.

I suppose, too, that I’m not taking into account that different rootstocks perform differently in various geographic areas. So a seedling of mine which does well here might not be so happy, say, in Florida. I begin to see why a few varieties of rootstock which are known to do well in particular areas is appealing to the commercial growers. Me, I’m lazy and do not winter protect. Some springs I end up pruning my roses to the ground. I like own-root because then I know if the rose comes back, it’s not the dreaded Dr!

Alicia