Topping Dahlias Page 4

Comments on this presentation by Alan A. Fisher

We hope to obtain pictures to illustrate Alan's approach to topping dahlias...The Webmaster.

Ben -- some comments on the nice new section on topping dahlias. The section says that in theory plants use up energy growing extra laterals. An alternative theory is that the extra growth makes the plant stronger and contributes to larger blooms. That is the theory I have heard more often. I am unaware of evidence to select between theories.

I often top late to delay the development of laterals to get my first blooms later. However, when I do, I always leave lower laterals whenever possible. The lower laterals bloom later than the higher ones. Because they have longer to develop, they should give larger blooms than higher laterals. I have never before seen recommendations to strip lower laterals and let higher laterals bloom. The plant has better stability if one lets the lower laterals develop.

Moreover, one can try to estimate blooming time. If one has a terminal bud, one can estimate when that bud would open. (See article in the June Bulletin in 2 of the past 3 or 4 years.) Count down leaf nodes. One can estimate 6 to 7 days for each set of leaves. If one selects a lateral 6 sets of leaf nodes down from the terminal bud, then one can expect the lateral from that leaf node to bloom 36 to 42 days later than the terminal bud. This procedure is useful in determining which leaf nodes to use when topping for a show. I would estimate more like 7 days per leaf node for AA and A and more like 6 days for B or BB. The exact timing varies with latitude (further north days are longer and thus development may be quicker). However, plants often develop faster in warm than in cold weather.

Thus temperature can also affect timing. When topping late, top as little as possible. It is not necessary to remove everything in the center. Indeed, when topping, I try to eliminate as little as possible to avoid getting a hole in the center. I then remove all side shoots from top leaf nodes as soon as I can. I check each plant at least twice a week and remove extra laterals as soon as possible -- unless I want to leave some for double topping or timing purposes.

I hope you and the CDS wives find these comments useful. Your web site is terrific and improving all the time. I am waiting for my handyman to finish working on my shade cloth and installing a staircase. However, if he doesn't come soon, I'll take new photos for you anyway... Alan Fisher