Do It in Your Dahlia Patch

Monthly advice from local growers

In June, things should start to get exciting.

Hopefully, you've planted your tubers and growth is visible above ground. Of course, if you planted plants, they should be well established by now.

During the next month focus on the following:
  • Keep checking to make sure your tubers are growing. On occasion, tubers will rot and show no signs of growth. If you don't see any greenery after several weeks, dig up the tuber carefully and see what's going on. Sometimes they are just slow. On the other hand, they may be rotting. In some instances, you may see a shoot come up and then not develop further. Tuber rot may also be the problem here. All suspect tubers and plants should be replaced; otherwise, there will be an empty spot in your garden. You can replant as late as the end of June and still get flowers this year.

  • When your dahlias reach the point where they have developed six pairs of leaves, pinch out the top. This will stimulate the growth of laterals from the area where each leaf joins the main stem. Sometimes laterals start growing at the bottom of the plant before six pairs of leaves develop. Remove these laterals. After pinching out the top of the dahlias, side dress the plant with about 0.5 lbs (about 3 hands full) of 5-10-10 fertilizer. Sprinkle the fertilizer in a 2-foot circle around the plant, cultivate lightly, and water.

  • In order to produce show grade flowers, the number of laterals allowed to grow on the plant needs to be regulated. The number of laterals recommended according to dahlia size is as follows:
    • AA -- 4
    • A -- 4
    • B -- 6
    • BB -- 8
    • All others -- 8 or more

    • Laterals should be removed starting at the bottom of the plant (i.e., if you want to retain 6 laterals, leave the ones that develop at the top 3 pairs of leaves.)

    • You will want to side dress your dahlias again with 0.5 lbs of 5-10-10 when the largest laterals develop two pairs of leaves. The procedure (described in (2) above) should be used.

    • Remember, you must spray your dahlias regularly to control pests and decease. I will address this subject further in my tips for July.

      Our goal is to have every member exhibit flowers at our annual show in September.