Lecture by Alan Chadwick in Saratoga, May 23, 1972
Lecture 4, Part 4.4
An Introduction to Alan Chadwick's Lectures and a Glossary of Terms
The full text of this lecture segment
Contents of this Segment:
Alan Chadwick here discusses the speciality culture of Dahlias; The propagation of Dahlias; Lifting and storage of Dahlias; Planting methods.
Villa Montalvo Lecture Series
Saratoga, California, 1972, Lecture 4,
The Totality of the Garden, Part 4
I would like now to deal very quickly with certain plants that are a great interest and importance in the garden, that everybody loves, and certain handlings and dealings with them. Some of you, of course, are completely au fait with these matters and you must forgive repetition. I want to talk for a moment about dahlias.
There are four conspicuous variations of dahlia, that is, the decorative dahlia which many people love because it’s as big as a plate. And it hangs its head down, and it lasts about two days in water and always looks like a collapsed maniac. Then there is the cactus dahlia, which is very fine and pointed, as you know, and very beautiful. It also has very poor lasting qualities as a cut flower but is very delightful, decoratively, in the beds, and has a long, long period of blooming. Then there is the pom-pom dahlia, which looks like an Elizabethan ruffle, and is slightly better for cutting, but again, doesn’t last very long; usually four to five days, at the most.
Then I want to introduce you, because it’s hardly known in America, to the lotus dahlia. And it’s unique… It’s really unobtainable again now because of import problems. And this is a very bad introduction of it because the lotus dahlia really does have to be disbudded to produce the stalk. But normally the stalk of this dahlia is four foot to a bloom, four foot long. And the lotus is straight up; you see the bloom is straight up. And it stands like that. And that bloom will last ten days to two weeks in water. And this is still the champion of the world. It’s been the champion of the world for eight years in Vienna, Paris, New York and London. It’s name is Gerry Hook. We will give tubers, next year, to anybody who wants them. It really cannot be purchased, and not true to name anyway. Then there is a yellow, exactly the same, known as Glory of Hiemsted. And this also has exactly the same qualities.
When I grew this on Long Island for those intolerable millionaires, out of bravado to their neighbors—they were always madly showing off to each other—they took a dozen of these to a New York florist and collected fifteen dollars for them, for a dozen blooms. So it gives you a little idea of their valuation. And this dahlia has different characteristics. And there are a number of others, such as House of Orange, Franz Joseph, Miramar and Bachelor, in different colors, but only those two are pure lotus, that is, having that enormous lasting quality and that upright long stem.
Now, they have characteristic of propagation. There are three ways of propagating the dahlia: One is from seed, whereby you would not reiterate any of this, ever. You would get something new, perhaps, and out of the majority you would go back to the origin dahlia, which is a kind of muddy apricot color. That’s the origin dahlia, and practically a single at that, of course. So the seed is no use to you at all, from that point of view, other than bringing about a new member. And you’ve got to raise thousands, hundreds of thousands, to do that.
However, the two other methods are very simple. One is, of course, from cuttings of shoots, struck in a striking bed, will root, and out of those roots will develop a tuber the first year, several tubers. And from then on, every one of those cuttings, and every one of those tubers, will be absolute identity of the origin parent.
The other method, of course, is the proper one, mostly employed by everybody for ordinary quantity production. And from Gerry Hook you can produce six tubers per annum out of every one you lift, next year. And out of Glory of Hiemsted, the yellow, you can produce anything from eight to twelve. So you see, you get a huge propagative explosion from this plant.
Now, all dahlias, whether they be the little dwarf dahlias, or they be this type, or any other, must be lifted every year. It is no good arguing the point and saying, “Oh, mine do beautifully.” They do, of course, because they are yours and because they are in your garden. But the true cultural method of improvement and looking after, that they must be lifted when they go into dormancy. And they must be lifted and put to dry on top of the soil during the day, and then they must be stored in a store that is very cool and dry. And they must not be stored totally dry. They should be stored in leaf or leaf mold, or some such matter that does not dehydrate. And I don’t mean peat moss. Peat moss is absolutely the wrong thing because it becomes sodden and is useless. But they should be buried in great piles in this stuff throughout the period of storage.
Now, the dahlia does stand… does have a long dormancy period: anything from three to five months. And the tubers should not dehydrate. An important note about dahlias is that they do not shoot from the tuber. They shoot from the base of the crown of the old stalk. When you cut your dahlias down, you should not cut them down to ground level. You should cut them down to about four inches of stalk left. Otherwise you are liable to do damage and to not rehabilitate the growth of the tuber. This is a very important note.
Now, they should all be stored… And they can be stacked on top of each other, but everybody knows that the dahlia is most succulent and damageable. It must be lifted with the utmost caution and handled with the greatest of care, more than any other plant of the garden. It needs great, great care in its handling. But they can all be piled on top of each other, with leaf, in this store. And, of course, this store should have an air current running through it. The only thing that it must not be… It must be frost-pervious. However, any low temperatures are perfectly satisfactory, and high temperatures must be avoided. And it should be dark. When they have been stored, and, according to the time that you want to produce your dahlia… And the answer is just that. You can have dahlias very early if you want to, or you can have them not coming into bloom until the beginning of the declination: in other words, July. You can do which you like.
That the dahlias should then be taken from the store, either totally or in sequences, which is a very good plan, of course, and they should always go onto striking beds. Now the striking beds should be started under glass for the very earlies, or outdoor for the laters. And it should simply be a small mound of loose, fragile, leafy soil. And they should all be stacked on this mound, which doesn’t need to be high, it’s just a mound. And that they should all be placed touching each other, and just covered, only just covered, with light, leafy soil; sandy, leafy soil. Not much in the way of soil: sandy, leafy stuff. And, of course, even… the stuff that comes from bogs, you know, from heather… … peat. The one thing to avoid is sphagnum. Sphagnum, as you know, contains much too much moisture. Then that mound should be watered. It should also, of course, be labeled as to what the variety is.
And within a month to five weeks, you will get shoots beginning. And when those shoots are two or three inches, the whole of those tubers should be carefully lifted with a prong. And now you need three very sharp knives and a carving board. And as you know, the dahlia planted is one of the deepest plants of the garden. They must go very deep, like the sweet pea. And it likes old fashioned soil, preferably prepared two to three months before planting time. Loves old soil, loves old gardens, old atmosphere.
You then place this bunch of tubers, depending upon the character of the plant… You have stored them just as you lifted them. And you have probably got a bunch of twelve to sixteen tubers all connected on one emblem. You place this on your board. And your object now, for classical division, is to produce one shoot to every tuber. It doesn’t matter if you have two shoots to three tubers, but don’t go beyond that. The classical is one shoot with one tuber. You can go up to two shoots to two tubers, or two shoots to three tubers if you have difficulty in your division. And remember that your division with your sharp knives must be: not through the tubers. You divide through the old stalk.