Life of the Dahlia-Chapter 4 April

It’s April 5, 2023, even though Spring is happening all around us, cold winter temperatures prevail! The next 10 days of weather projections predict a continuing wintery pattern with no sign of warming temperatures conducive to warming soils. Our tubers, however, are waking up in storage and are showing signs it’s time to plant. Spring is busting out all over, but conditions aren’t quite ready to welcome the new beginnings for the life of the dahlia.

The Pacific Northwest has many microclimates that will determine when you can plant your tubers. My yard, even with full sun exposure tends to be a little cooler than someone who may live closer to sea level. Although temperatures are warming up, nighttime temperatures are still very cool. For most of us west of the Cascades, the first week of May is the perfect time. For those of you living in a cooler area you may have to wait until June. The key to successful planting is the right soil temperature of 55 degrees!

In the meantime, for those of you who need to plant something start your tubers in pots or trays. In the past I have taken tubers from storage and placed them in trays covered with wet shavings. The tuber eyes start to pop, and roots begin to emerge. You can also start some of my larger varieties in pots. I then transplant when the PLANT has three sets of leaves. I take lots of cutting and plant the tubers and cutting plants at the same time. If the soil temperature is right, I will see tuber sprouts emerging and the cutting plants start growing. If the weather is wet and cool, the tuber and cutting plant will just sit there until the soil temperature is right.

Now that you’re ready to plant, here are the basic guidelines to follow. Spacing. Many new growers ask me how far apart they should plant their tubers. For me I always plant 24 inches apart. For the giant varieties I would maybe space up to 36 inches. For the smaller varieties 18 inches will work. Proper spacing gives you room to groom and cut your blooms.

Drive support stakes into the ground for the taller varieties or use tomato cages for the smaller dahlias. Dig a hole 5-6 inches deep. Before planting the tuber, it is time to add some fertilizer and mix thoroughly in the hole. Over the years I have created a mixture of 2 to 3 TBLS of 10-20-20 fertilizer,

1 TBLS bone meal and 1 TBLS Epson salts placed in each hole. Everyone has special additives they like as well. These might include alfalfa meal, kelp meal, compost, and other stuff.

Prior to planting you need to create a label for each of varieties you’re going to plant. Most growers use plastic labels and indelible ink, industrial grade non-fading markers like Sharpie to label tubers. Some use label printers, creating labels that can be used year after year. Labels should also include bloom size, type, and color. As a backup, some growers also create a garden map with dahlias names if labels disappear.

Once mixed, place the tuber horizontally with the eye pointing up, two inches from the stake. If a dahlia sprout breaks off, no worries, the tuber will grow another. Cover with 2 inches of soil. Shallow planting like this will allow moisture and the heat from the sun to help the tuber start to grow. As the plants grow taller you can fill in the remaining 3 to 4 inches of soil. Good luck planting but be patient for the right planting conditions!

There is still time to score some dahlias online and at tuber sales this month. Log onto to the American Dahlia Societies web site dahlia.org and click of 2023 Local Societies Tuber/Plant Sales.