Time to take cuttings & plant seeds.
Now is time to take your dormant tubers out of hibernation and bring their boxes, bags or buckets into a warmer spot to germinate. Most dahlias sprout in temperatures of 62-65 degrees.
You can begin potting up your tubers in preparation for taking cuttings – or for later planting in the ground.
While a greenhouse is nice, you don’t need one in order to take cuttings. A table with a fixture or two of inexpensive fluorescent lights hung over the table is sufficient. Make sure the lights can be adjusted so the plant growth is no more than 3- to 4-inches from the light; otherwise the plant will stretch. Also, using a plastic cover over your cuttings will help keep moisture in so you don’t have to water your cuttings every day.
Use a good peat-based potting mix and add half as much sharp sand or perlite. Make sure the mix is damp (not wet) and pot the tuber so the eye is sitting just above the medium. You can bury the tuber, but you will have to move the medium aside to cut the stem close to the tuber. Cutting can be done when the plant has 2 sets of leaves.
Use a disinfected blade, scalpel or X-acto craft knife to cut the plant away from the tuber. Remove the bottom set of leaves and place the cut stem in the potting mix. You can use a rooting hormone if you wish, but it is often not necessary. Thin stems are better for rooting; thick stems often are hollow and difficult to root. Rooting should take place within two to three weeks, depending on the variety.
Some people use milk cartons for jump starting; others use yogurt containers; still others use 1-gallon pots, oasis cubes or individual cell trays. Whatever your choice, just make sure your containers have drainage holes.
If you saved seeds from last year’s beauties, March is also the time to place them on a wet paper towel and cover them with another damp paper towel. When you see sprouts, transfer individual sprouts into 4×4 pots of loose potting soil with lots of perlite and put the pots in a sunny window or under shop lights. These are your genetic lottery tickets for next year!