Some Ideas In Plant Propagation/ Cuttings And Grafts (Mostly Roses)
By Ralph S. Moore, 2519 East Noble Ave,. Visalia, CA 93292
Most likely most of what I am about to say is "old hat" to many of you. However, we can all learn something new or give an old idea a new twist, All too often we see something or got an idea but fall to follow it through. Sometimes we are too busy to bother or the idea fails to "click". Often we are just not ready or have no need at the time.
We know how to do many things in our business but someone is always coming up with a different idea or a new need arises. Often an idea which may have been impractical at-the time can come to life because of new materials. Rooting hormones, misting, plastic materials, etc. are some of the ideas which have made older ideas practical.
For many years we have worked at propagation (mostly roses) and have come up with several inovations some original, some borrowed. Some ideas come about by accident and others out of necessity. Now I would like to go down my list of helpful ideas for the propagation of roses and other plants. I have, and still do, worked with other kinds of plants. My plant breeding work has covered a wide range of interests. I started with roses and they are still a top priority with me. But I have worked with such plants as Zinnia, cosmos, plum, cherry, gloriosa daisy and crepe myrtle.
In this work I have had to learn and use numerous ideas and techniques in plant propagation. First, there are seeds. Each species and (often) variety has special demands. In my work with dwarf crepe myrtles harvesting and cleaning seed has its special requirements. I learned that often some of the best parents shed their seed too soon or the seed capsules would not open properly, in which case it was necessary to crush the dried capsule to release the seed.
Some plants propagate easily from either soft or hard wood cuttings. Others need special care, preparation, timing, planting depth, light and moisture conditions. Some of these are learned by experience or through reading or training. Often the grower learns by close observation. Often the plants themselves are trying to tell us something and it pays to become a keen observer.
In my work I have dealt with propagation from seeds, from cuttings and by grafting. So I would like to make some observations and suggestions; tell you some of my experiences in the field of plant propagation.
First as all propagators know or must learn, there are several different kinds of cuttings and grafts... different methods to make another plant. Many plants can be propagated easily and inexpensively from hard wood (dormant) cuttings. But I want to discuss mainly the propagation of roses ( and other plants) from soft wood or "green" cutting material. By"green" I mean wood of the current season's growth with leaves. These may be made and rooted over most of the growing season if given proper care and conditions.
In roses (miniatures especially) the soft growing tip and material immediately below this makes excellent cuttings and roots quickly. Cuttings may be 2 to 4 inches in length. We do not remove leaves. Bottom cut is made just below the eye or bud. If cut even 1/4 inch below the eye the cutting takes longer to root. There are also several other ways the cuttings can be made or prepared for rooting.
A small length of twig (I like cuttings with 2 or 3 eyes (and leaves).
Shorten the leaves to save space and help prevent leaf drop. It is essential
to have at least one leaf on each soft or green cutting.
Another propagation method is the budded cutting. One must have available a healthy, vigorous understock plant, producing long succulent canes suitable for budding. If done late in the season and cuttings are to be used "dormant" all leaves may be stripped off the cane before budding. Buds are allowed to heal in and the canes made up into cuttings during the winter. Remove all unwanted eyes before planting. Good bushes can be grown in one season by this method. If the canes are to be made into cuttings as soon as buds take at least one leaf must be left on each cutting. Another reason to use the cane bud method is to "store" buds of some new or rare variety (on canes) for later use ; budding or grafting when it is too late in the season for normal (field) budding/ buds are too small/ or too soft.
To hasten rooting of cuttings the stock plant (from which cutting is to be made) may be wounded by girdling (making a knife cut around the branch or twig) and covering with black tape until the callus beneath the tape is well formed. Remove tape and plant in rooting media. Another type of wounding is to remove a bit of bark 1" to 2" long from one or both sides of twig and cover with black tape as above. These methods work with rose, camellia, redwood, plum, metasequoia, etc.
We grow quite a number of miniature tree roses and now use a budding technique which I saw in South Africa several years ago. Instead of making a T cut and slipping the bud under the bark flaps, this method only requires a very shallow cut to remove a sliver of bark (we leave a bark flap about 1/4" long at top of this cut) then a similar sliver (skin bud) is laid over the cut, tucked under the short flap, then tied in with parafilm. Works very good for us. Another variation on the above, when used outdoors in hot weather or if the bark is thick, is to tie bud in with parafilm then overwrap with a rubber budding strip. This holds for longer time and in closer contact when the stock and/ or buds are heavier thus insuring a good take. I have done this on dormant cherry with 100 % success.
To produce many cuttings from a rose plant we have used the following method (works on Hybrid Tea, Floribunda, etc.). Grow stock plants in containers and keep in vigorous soft growth. As flower buds appear they are pinched off to force growth from eyes (at each leaf) below the bud. One to three soft, single eye cuttings (as mentioned earlier) may be taken as soon as growth from each leaf reaches 1 and 1/2 to 2 inches in length. In a few more days another cutting or two may again be ready. This process is repeated and new canes from the base arise to replace those used up. If watched carefully many cuttings can be produced in this way, thus increasing a variety rather quickly.
Another method I use to hasten my breeding ( and shorten testing and production time on a new rose) is to use seedlings from my breeding. There are usually a number of discarded climbers which do not bloom or flowers are poor. These can be used as "clean, virus free" understocks on which a promising seedling may be budded. To test out a possible hanging basket or groundcover variety I usually bud at 24 to 36 inches. For others 8 to 12 inches is adequate. This gives a good idea of the shape and growing habit of a new variety, its flowering habit and can supply more propagating wood in a short time.
A variation on the above is to use rooted multiflora rose cuttings grown from clean virus free material. I like to have a plant which is grown from a de-eyed cutting which heads out about 6 or 8 inches above the soil line (in pot). From this numerous shoots will grow. I select the strongest, removing all eyes possible up to the height at which I wish to bud. This fast growing cane is easily budded and take is usually excellent.
Roses can be grown by grafted cuttings in which a short cutting (multiflora or any easily rooted stock) about 4 or 5" long is made, leaving 1 or 2 leaves at top. All other eyes are removed. Then a deep slanting cut is made in the understock (about 1 inch from base) into which a wedge shaped graft is placed. This graft may have only one eye with leaf. We wrap with parafilm as the graft heals much better.