The Dahlia of the Future: Cultivation, Improvement, and the Search for Perfection

Originally published as The Evolution of the Dahlia: Chapter Eight (1925)

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.

Dahlias Now and the Dahlia of the Future closes the numbered sequence in this edition, but it did not close Broomall’s surviving numbered series, and there is no evidence that he intended it as the conclusion of his projected book.

The first half returns to one of his recurring questions: why an established variety sometimes performs badly. Broomall rejects the idea that a double dahlia has permanently “gone back” merely because it produces imperfect flowers. He argues instead that growers must investigate soil condition, culture, climate, insects, disease, root development, heat, and drought before blaming the old tuber or discarding a cultivar. Golden West becomes his principal example: Broomall reports obtaining fully double flowers from poor roots, old roots, propagation roots, and green plants alike.

From the condition of existing plants he turns to the future of the flower itself. Better dahlias, he argues, require better knowledge, better culture, more careful observation, and the sharing of experience. Because every advance raises the standard by which the next generation is judged, he sees no fixed endpoint to improvement. His ideal future dahlia need not be abnormally large, but it must have broad usefulness, commercial value, and above all color capable of commanding attention.

Its position at the end of this reconstructed sequence is editorial rather than authorially specified. Broomall’s intended conclusion is unknown. Chapter Eight closes the sequence because its final forward-looking movement provides the strongest surviving conclusion to the numbered material, not because the chapter can be shown to have held any special final status for Broomall.

The text printed here is from J. J. Broomall’s 1925 Dahlia Guide.

Before considering the “DAHLIA OF THE FUTURE” I propose to say more about the Dahlias we now have.

I am aware that many Growers will not agree with what I say in regard to the continuity of Double Dahlias, but I propose to state the facts as they appear to me, and if you think that I am wrong in my deductions I will call your attention to the fact that I get “RESULTS.”

The Proof of the Pudding in this case is that I get the goods.

Customers write me that certain well known Dahlias failed to make perfect flowers, and speak of throwing away their roots and obtaining fresh stock.

Now I regard this as a foolish custom, and an unnecessary waste of good roots.

If a Double Dahlia fails to come perfectly double there is always a CAUSE for it, and in a great majority of cases the trouble does not lie with the tubers, but in their environment.

Frequently the fault lies with the CONDITION OF THE SOIL, the treatment they receive, or it may be due to climatic changes and sometimes to insects or disease.

Growers should understand that Nature provided tubers to preserve the germ of life from one season to the next, and as a rule the Dahlia is drawing but a small portion of its nourishment through the fibres of the old tuber by the time it has reached the blooming stage.

For by that time the newly formed young tubers are well developed, and the plant is receiving by far the greater part of its sustenance through its newly formed root-system, and a very small per cent through the more hardened fibres of the so-called “Mother-Root.”

In my opinion what the old tuber may or may not have done the previous season has very little to do with the quality of the flowers produced.

Where Green Plants are used the sap is ALL flowing through the young tubers as there is no old tuber on the plant.

Some Dahlias have a tendency to simply increase the size of the old tuber and not throw out any young tubers at all; this is more likely to occur when two year old tubers have been used.

The way to prevent this, and to force the old tuber to produce new ones is to cut off two-thirds of the old tuber.

In most cases if an inch of the fleshy part of the tuber is left attached to the eye, or to the neck it will be sufficient.

Tubers so cut should not be planted until the cuts have had time to heal.

If powdered sulphur and lime is applied to the cut surface, it will prevent possible decay in heavy soils.

Tubers cut in this manner will be slower in starting into growth, as it will be necessary for adventitious rootlets to start around the end of the cut tuber, and they will not start as quickly as they will from the outer end of an uncut tuber.

To illustrate how little the old tuber has to do with the quality of the flowers, I sold so close on the Golden West last Spring that I had scarcely any good roots left to plant, and only a few hundred green plants.

So I planted all the poor roots I could find including some that were three or four years old, and wound up by planting the roots I had used for propagation.

Now as to the result: if there was one of those Golden West that did not produce perfect flowers full to the center, I failed to see it.

In 26 years of Dahlia growing I have never discarded a Dahlia for having “Gone Back,” as far as doubleness was concerned, and if visitors to my garden have seen any evidence of any having “gone back” they certainly made no mention of it.

I believe in treating my Dahlias right, and here in part is the treatment they receive.

In the first place I aim to have the ground in perfect condition before I plant, and I believe in frequent and thorough cultivation.

I have said in my cultural notes that “deep cultivation should cease when they begin to bloom:” but I want to explain that this should only apply to the ground within eight or ten inches of the plants.

I cultivate in the middle of the rows (which are four feet apart) as deeply as the Horse-Cultivator or Heavy Hoe can be driven until I cease irrigating, which is generally about the middle of October.

Some will tell you that the feeding roots are close to the surface after the Dahlias begin to bloom. That may be, but they should not be allowed to be there, and frequent and deep cultivation will keep the most of them further from the surface where their environment is much more favorable for a sustained healthy and vigorous growth.

What happens to the roots that are close to the surface in times of extreme heat and draught?

Why, a large portion of them shrivel up and perish; they are literally “cooked.”

Is it any wonder then that the blooms are poor?

Some prominent growers advocate mulching.

I DO NOT BELIEVE IN MULCHING.

In the first place the litter that is generally used for mulching makes an excellent harbor for insects, and in the second place it prevents thorough cultivation of the soil.

The best mulch of all is the dust mulch that is produced by the pulverization of the surface soil.

Some of my friends say the reason my Dahlias do well is because I have such fine soil; this is a mistake.

My soil is no better than theirs in most cases, and is no better than other millions of acres in California.

I try to keep my soil in good condition and the Dahlias act accordingly.

My fellow growers, the future of the Dahlia depends upon US.

We should not only strive to improve upon existing varieties, we should learn all we can about their habits and requirements, and give others the benefit of what we discover.

In my opinion, great as has been the improvement of the Dahlia in the last thirty years, we may expect to see still greater progress in the future.

The perfect Dahlia, the Dahlia that will score 100 has not yet been produced, and it is doubtful if many of us will live to see such a Dahlia, for as it continues to be improved the standard by which it is judged will be raised accordingly.

We have Dahlias now that if they were to be judged by the standard of excellence of twenty years ago might score 100 points, but now that we have them we can see where they still fall short of perfection.

I can see no limit to the possible improvement of this wonderful flower; in fact it seems to me the only limit is our knowledge of it.

While there is a craze at present for the largest flowers obtainable, it is my opinion that the Dahlia of the future may not be a flower of abnormal size, but it must be a good flower for all purposes.

Especially must it be a good commercial cut-flower, for that is the Dahlia that will most appeal to the general public.

There are millions of people living in the Cities who cannot have gardens of their own, and the Dahlia, because of its large size and brilliant colors, has won its way into the esteem of the general public to a greater extent I believe than any other flower.

The increase in the sale of Dahlias in the cut-flower market in the last few years has been many hundred per cent and it is going ahead faster than ever.

The greatest room for improvement of the Dahlia is in the coloring.

When we enter a field of Dahlias there is always one or two that because of their unusual color attract immediate attention, and the Dahlia of the future (combined with its other good qualities) must be one of such transcendent beauty of color that it will compel those who see it to linger long and feast their eyes upon its incomparable beauty.

A flower of such unsurpassable loveliness that we will feel like taking off our hat to the DAHLIA OF THE FUTURE.

J. J. BROOMALL.

1. “Gone back.” Broomall uses “gone back” for the belief that an established double cultivar has permanently lost its inherited capacity to produce fully double flowers. He rejects that conclusion when cultural, environmental, pathological, or physiological causes have not first been investigated.

2. Old tubers and the new root system. Broomall says that by flowering time the old tuber supplies only a small part of the plant’s nourishment and that “by far the greater part” comes through the newly formed root system. Chapter Six had used the more specific figure “more than 90 per cent.” The two formulations are preserved separately rather than harmonized.

3. Cutting the old tuber. Here Broomall recommends removing two-thirds of an old tuber. Chapter Six had advised removing at least three-fourths. The difference is his own and has been preserved rather than standardized into a single instruction.

4. “In 26 years.” Broomall’s statement that he had never discarded a dahlia for “going back” in twenty-six years is preserved as printed. It does not align exactly with his later recollection that he first raised dahlia cuttings about 1897, or with later statements of twenty-seven years and more than thirty years. The chronology remains unresolved.

5. Mulching. Broomall strongly opposes surface litter used as mulch within his cultivation system, chiefly because he believes it shelters insects and interferes with cultivation. His later use of compost, humus, leaves, weeds, and other organic matter incorporated into the soil does not by itself establish a reversal of this position.

6. The moving standard of perfection. Broomall’s “score 100” argument treats perfection as a moving target: improvements that might once have seemed ideal raise the standard by which later dahlias are judged. That principle underlies his claim that there can be no fixed endpoint to the improvement of the flower.