Starting dahlias from tubers in January and February

Starting dahlias from tubers in January and February is a great way to get a head start on the growing season, especially in climates where winters are long and cold. Here are some steps to successfully start dahlias from tubers during these months:

• Choose Healthy Tubers: Select tubers that are firm and plump, without any signs of rot or damage. Each tuber should have at least one “eye” or growth point from which the new plant will sprout.
• Prepare the Planting Medium: Use a well-draining potting compost mix such as John Innes number 1  in a tray or pot. The soil should be moist but not waterlogged.
• Plant the Tubers: Lay the tubers horizontally in the soil, with the eyes facing up. Cover them with about 1-2 inches of soil. The top of the tuber should be about an inch below the soil surface.
• Provide Warmth and Light: Place the tray or pots in a warm, bright location. Dahlias need warmth to start growing, so a temperature of around 60-70°F (15-21°C) is ideal. If natural light is limited, consider using grow lights.
• Water Sparingly: Water the tubers lightly after planting and then only when the soil starts to dry out. Over-watering can cause the tubers to rot.
• Watch for Sprouts: In a few weeks, you should see sprouts emerging from the soil. Once they appear, ensure they receive plenty of light.
• Transplanting: Once the danger of frost has passed and the sprouts are a few inches tall, you can transplant them to their final location in the garden.
• Gradual Acclimatisation: Before transplanting them outdoors, acclimate the dahlia plants to outdoor conditions by gradually increasing their exposure to outdoor temperatures and sunlight.

Remember, starting dahlias indoors requires patience and attention to detail, but it’s a rewarding process that leads to beautiful blooms in the summer and fall.

Increasing your dahlia plants through cuttings 

Taking cuttings from the shoots that dahlia tubers produce is an excellent way to propagate more plants. This method, known as softwood cutting, involves taking a piece of the young, tender growth and encouraging it to form roots. Here’s how to do it:

• Timing: The best time to take cuttings is when the shoots from the tubers are about 3-4 inches tall. This usually happens a few weeks after the tubers have started sprouting.
• Selecting Shoots: Choose healthy, vigorous shoots. Look for those that are straight and have a few sets of leaves.
• Preparing for Cutting: Fill small pots or a tray with a mixture of peat and perlite or a similar well-draining, sterile potting mix.
• Taking the Cutting:
  • Use a sharp, clean knife or scissors to cut the shoot just below a leaf node (where the leaf meets the stem).
  • The cutting should be about 2-3 inches long and include at least one set of leaves at the top.
  • Remove the lower leaves to expose a bare stem, which will be inserted into the soil.
• Planting the Cutting:
  • Make a hole in the prepared potting mix with a pencil or similar tool.
  • Insert the cutting into the hole, ensuring that the area where the leaves were removed is buried.
  • Gently firm the soil around the cutting.
• Creating Humidity: Cover the pot or tray with a clear plastic bag or place it in a mini greenhouse to create a humid environment. This helps prevent the cutting from drying out before it can root.
• Care for the Cuttings:
  • Place the cuttings in a warm, bright area but out of direct sunlight.
  • Keep the soil moist but not waterlogged.
  • Ventilate occasionally by opening the plastic cover to allow fresh air in.
• Root Development: In a few weeks, roots should develop. Gently tug on the cuttings to feel for resistance, indicating root growth.
• Transplanting: Once the cuttings have rooted and grown strong enough, they can be transplanted into individual pots or directly into the garden after the risk of frost has passed.
• Acclimatisation: Gradually acclimate the new plants to outdoor conditions before planting them in their final location.

Propagating dahlias through cuttings not only gives you more plants but also creates clones of the parent plant, ensuring that the flowers will be identical in colour and form.

Images from Depositphotos