Stunted Dahlia Plants: Propagation, Cultivation, and “Running Out”

Originally published as The Evolution of the Dahlia: Chapter Six (1923)

Original text by J. J. Broomall is in the public domain.

Compilation, editorial notes, introduction, biography, and revised text copyright © 2026 by Steve K. Lloyd. All rights reserved.

In Stunted Plants, Propagation and Cultivation, Broomall interrupts his planned discussion of color because he believes misunderstandings about dahlia culture require more immediate attention. The chapter therefore begins as a practical corrective, but its deeper subject is the familiar problem of distinguishing temporary poor performance from permanent change.

Broomall argues that weak growth and imperfect flowers may result from soil condition, moisture, climate, propagation history, old tubers, or restricted growth. He repeatedly insists that the grower should investigate causes before condemning a cultivar as permanently deteriorated. Here he also makes an important limitation explicit: when he says that a dahlia does not permanently “go back,” he is speaking of doubleness, not color.

The chapter develops Broomall’s practical method in unusually concrete terms, from deep soil preparation and repeated cultivation to propagated plants, “Mother Roots,” newly formed tubers, and regional differences in cultivar performance. Its placement here continues the investigative movement of the preceding chapters, although that continuity is editorial rather than an explicitly marked serial transition.

Broomall does, however, leave one useful forward signpost of his own: he explains that he had intended to discuss “Color in Dahlias” but postponed the subject. That postponed discussion follows later in this reconstructed sequence.

The text printed here is from J. J. Broomall’s 1923 Dahlia Guide.

(Explanation: It was my intention to devote this chapter to “Color in Dahlias,” but there appears to be so much misunderstanding in regard to the habits, action and requirement of Dahlias, that I am going to give more space to cultural talk.)

There are certain basic principles in the culture of this great flower that I propose to repeat, reiterate, and continue to repeat until I make my method of culture understood, if it becomes necessary to take up two-thirds of the space in the “guide” in order to do it, as I believe a better understanding of the Dahlia to be of greater importance than anything else.

When I buy a machine with which I am not familiar, I reason about it in this fashion—If some one had brains enough to make the machine, I should have brains enough to use it, if the instructions are sufficiently explicit.

And to you, gentle reader, I would say, if some one has produced a flower of great size or rare beauty, you should be able to successfully grow it, if its requirements as to culture are thoroughly understood.

And now as to “Stunted Plants,” and imperfect flowers, these may be due to a variety of causes among which are unfavorable climatic conditions, lack of moisture, too much moisture, and what I believe to be the most frequent cause of all, UNFAVORABLE CONDITION OF THE SOIL.

I sold a neighbor two dozen Dahlia tubers last Summer. These were planted at the same time as some of mine were, in soil as fertile as mine.

Any soil that will grow weeds several feet higher than my head WITHOUT cultivation should produce fine Dahlias WITH GOOD CULTIVATION.

Part of those Dahlias grew from two to three and one-half feet high, and bore a few small flowers. Some only got up a few inches and failed to bloom at all.

Now why was this?

I advise that if the ground is not sufficiently moist that it should be wet TWO feet deep. That ground was only wet a few inches deep.

I say the ground should be plowed, or dug as deeply as possible. That was only plowed five or six inches in depth.

I say the soil should be thoroughly pulverized. That was left in hard lumps, but was smoothed on the top so that it APPEARED to be in better shape than it really was.

My Dahlias planted at the same time were put in ground that had been plowed as deep as possible and thoroughly harrowed early in the Spring, and when I was ready to plant it was plowed and harrowed the second time.

In addition to this I dig the ground as deep as possible and thoroughly pulverize it from one to two feet in width when I plant, so that when the tubers are put in the ground it is in IDEAL CONDITION, and they just cannot help but grow.

After they are well started I cultivate with a horse-running cultivator as deep as it will go, about every ten days or two weeks.

My last cultivating was done this year, September 19th, by which time many of the plants were so large that it was difficult to go through them with a horse without breaking some of them.

When I can no longer cultivate with a horse, I use a hoe. Not a light garden hoe, but a heavy “Planter’s Hoe,” and instruct my men to hoe lightly near the plants, and as deeply as possible in the middle of the rows, so that there is an abundance of loose soil as mellow and as finely pulverized as an ash heap.

With the soil in such condition the feeding rootlets can and do reach out and obtain all the plant food they need.

And the result—why, from the latter part of September until Thanksgiving my gardens were a joy to behold, a kaleidoscopic mass of colors.

My plants were not only two or three times larger than my neighbor’s, but the flowers were fully twice as large, and many times as numerous, plant for plant.

I have no “Runts,” no flowerless plants, no failures among thousands of blossom-laden plants.

True some of the propagated plants will throw imperfect blooms at first, but as the plants increase in size and vigor, “get on their own feet,” as it were (when conditions are IDEAL they seldom fail to do this), they will generally improve until they produce perfect flowers.

I do not believe that a Double Dahlia ever “goes back.” When I say this I refer to the DOUBLENESS of the flower, not to the COLOR, which is a different matter entirely.

If a Dahlia fails to make perfect flowers there is always a CAUSE for it, although it may sometimes be difficult to determine what the cause is.

Climatic conditions I believe to be one of the causes as yet but little understood. Sudden changes of temperature, especially to extreme heat, may cause a contraction of the fibres that will restrict the flow of sap (the life-blood of the plant), and this would certainly prevent the perfect development of the flowers.

The planting of old tubers, “Mother Roots,” as they are called, is another cause of deterioration, and I do not believe in planting them; but even they can be successfully used if at least three-fourths of the tuber is cut off, and the cut allowed time to heal before being planted.

When they are cut in this manner the plants are forced to throw out new tubers from the base of the sprout, with the result that the plants will soon be drawing more than 90 per cent of their sustenance through the newly formed tubers, so that the remnant of the old tuber, having served its purpose, will be practically in the discard as far as its influence on the growing plant is concerned.

Plants grown from cuttings will sometimes make single or semi-double flowers when they first begin to bloom, but it has been my experience that if the soil is in proper condition so that the plants can readily obtain all the nourishment they can assimilate, they will rapidly increase in size and vigor and will soon produce perfect blooms.

It does seem to me to be absurd, and a useless waste, to throw away roots because the plants have made imperfect flowers.

Nature created tubers for the purpose of preserving the germ of life from season to season.

The heredity of the plant determines the character of the seed, and if a seedling produces perfect double flowers two seasons in succession, that Dahlia will never lose its character.

If it fails to come good in after years, it has not “gone back” permanently, but has only failed temporarily, and there is ALWAYS A CAUSE FOR IT. It is up to us to find out the CAUSE.

I have never discarded a Dahlia for having “run out” as far as doubleness was concerned.

I have seen Golden West a failure, and Helen Durnbaugh come perfectly single, yet I planted the tubers from those plants, and this year they were as perfect and double as ever.

It should be borne in mind that it is the young tubers, the newly formed root systems, that provides the sustenance for the plant, and what the old tubers may have done or failed to do the previous season has very little to do with the production of flowers this season.

If the thousands of delighted visitors who viewed my gardens saw any evidence of “run out” Dahlias or “runts” they certainly made no mention of it.

The influence of changes of climate on the habits and color of Dahlias is a never-ending study, and he who keeps his eyes open may always learn more about them.

As a rule I believe that Dahlias bred in a hot climate will stand more heat without deterioration than those raised in a cooler region.

But it seems that there are exceptions to every rule; take Dorothy Durnbaugh for instance: Here in its native place it is one of the weakest growers and a shy bloomer, yet in many parts of the East it has proved to be very satisfactory.

Many of the Cactus Dahlias of English origin are not a success here, and I think the change from a cool environment to a much warmer and dryer one has a great deal to do with it; but here again there are exceptions, for it would be hard to find more satisfactory varieties, for instance, than F. W. Fellows, or that old standby, the Countess of Lonsdale, and others I might mention.

Yours for the better understanding of the Dahlia, and BETTER DAHLIAS.

J. J. BROOMALL.

1. Doubleness and color. Broomall explicitly limits his claim that a double dahlia does not permanently “go back” to the doubleness of the flower, distinguishing color as “a different matter entirely.” This qualification narrows the broader language of the preceding chapters and anticipates his later discussion of color variation.

2. Climate, “fibres,” and sap flow. Broomall attributes some imperfect flowers to sudden temperature changes that contract plant “fibres” and restrict the flow of sap. This explanation is preserved as part of his historical physiological reasoning rather than as a statement of modern plant physiology.

3. Old tubers and “more than 90 per cent.” Broomall states that a plant will soon obtain “more than 90 per cent” of its sustenance through newly formed tubers after most of the old tuber has been removed. The percentage is preserved as printed, but the surviving text does not establish it as a measured physiological value.

4. Heredity, seedlings, and clonal continuity. Broomall writes that “The heredity of the plant determines the character of the seed,” then moves from the inherited character of a seedling to the later stability of that named variety through tuber propagation. The conceptual imprecision is preserved rather than silently reconciled with modern distinctions between sexual inheritance and clonal propagation.