How To Grow a Dahlia Flower

Growing a dahlia flower always seemed like this mysterious, complicated thing that was beyond my gardening skills, but I discovered it is easy to plant and grow a dahlia. Last year Longfield Gardens sent me several dahlias to try in the test-garden and I found out that they are trouble-free if you treat them like a flowering annual in your garden. My discovery: Easy + Flowery = Super-Duper Flower Power!! Plant dahlias after the last frost from early spring until mid summer for blooms all through the late summer and early fall garden season.

According to the handy-dandy guide on the Longfield Gardens website, dahlia planting and growing is simple (see instructions below) —

PLANTING IS AS EASY AS 1, 2, 3

1. Dig a hole to 4-6” deep in well-drained soil.
2. Set the tubers in the hole horizontally, with the stem facing up.
3. Water weekly if the weather is dry. Sprouts should appear in 2-4 weeks.

TIPS FOR GROWING DAHLIAS

• Choose a sunny spot. Dahlias bloom best in full sun.
• To give your dahlias the best possible start, improve the soil by adding compost and an all purpose (5-10-5) granular fertilizer when planting.
• Dahlia tubers should be planted 4-6″ deep. Position the tubers so the sprouts are facing up. If there are no sprouts, plant the tubers horizontally.
• Once your dahlias are 8-10″ tall, start fertilizing them with liquid fertilizer every two to three weeks.
• When the first flower buds appear, cut back a couple of the tallest stems. This will help the plant fill out and produce more flowers.

(Photo credit Longfield Gardens.)

When planting, I only put a little organic fertilizer in the planting hole and did not add the suggested granular fertilizer mentioned above and they still exploded with blooms all season. In fact, high nitrogen fertilizers will produce a lot of greenery and not as many flowers per stem. Preparing the soil by loosening it and enriching it is a great way to help your dahlias along.

Dahlias have the wonderful attribute of blooming non-stop when planted in a sunny spot, but water needs are dependent upon your regional rains. Mulch plants after the first sprouts appear – mulching too soon will keep the soil cooler and the tubers prefer a warm soil. While they can attract bees and butterflies, they are not known as a bee-attracting powerhouse. With this in mind, I planted them near other pollinator attracting plants to balance out the garden with color and usefulness. Planting the dahlias with my Will Rogers Super Giant Zinnias turned out to be a brilliant combination as the bold colors went particularly well with the large red hummingbird attracting flowers. Try growing dahlias in your garden and expect lots of beautiful flowers.