How to grow dahlias from seed

If you’re like most gardeners, you probably wait until the last minute to start thinking about your summer garden. But if you want to include dahlias in your plan, it’s not too late! You can actually grow these beautiful flowers from seed. It may take a little longer, but the results are worth it. In this blog post, we’ll show you how to do it. So, get out your gardening gloves and let’s get started!

Introduction to growing dahlias:

Dahlias are native to Mexico & Central America

– They come in a wide variety of sizes, shapes, and colors

– Most dahlia tubers produce only one flower per plant, but there are some varieties that yield lots of smaller flowers. If you’re looking for something different than the same old bouquet this summer, consider planting dahlias!

Suggested Dahlia varieties:

-Dwarf varieties grow 8-12’, good for containers.

-Standard dahlia varieties range from 12″ to 5′, depending on variety. They will need staking or a large container.

-If you live in a warmer climate where the tubers can be left in the ground year after year, try tiny Polonia dahlias that only grow 4-8″. These plants are very easy to care for and produce lots of beautiful blooms over a long season!

When to plant Dahlia tubers:

-You can grow dahlia tubers indoors anytime between February and July.

-Once the danger of frost is gone, you can transplant your new plants outdoors. But don’t wait too long–dahlias are very sensitive to cold weather, so planting them too late in the season will not allow them enough time to develop strong roots before winter sets in. If this happens, they won’t produce flowers next year!

Where to plant Dahlia?

-Dahlias need full sun and well-drained soil.

-If you’re planting in a container, choose a pot that is at least 12″ deep.

-Since dahlias grow tall, they will need strong support–try placing stakes or metal posts around the base of the plant before putting it into the ground. You can also try staking your dahlia as it grows using twine or garden netting.

Soil temperature influences Dahlia growth?

-Warmth is needed for Dahlia seed germination and early growth, so start seeding indoors in early spring.

-Once the danger of frost has passed, you can transplant your dahlias to their permanent home. Be sure to work some compost or other organic matter into the soil before planting. This will help keep the roots cool and moist even when it’s hot outside!

Watering Dahlia:

-Like most plants, dahlias need plenty of water at each stage of growth–especially during flowering and tuber formation. During this time, be careful not to overwater them because excess moisture can cause root rot and kill off your plants!

Fertilizing Dahlia:

-When growing from seed, start feeding your plants with an all-purpose fertilizer about 3 weeks after germination.

-Once your dahlias are in their permanent homes, fertilize them using a balanced formulation (look for something that is 10-10-10) every 2 to 4 weeks during the growing season–more often in hot weather or if you notice any yellowing of leaves. You’ll probably need to reduce this frequency when the plants are dormant.

Dahlia Pests & Diseases:

-Aphids are one of the most common problems facing dahlia gardeners–they attack the foliage, causing stunted growth and curling leaves. To control these pests, treat affected plants with insecticidal soap or neem oil just before summer rains.

-Petunias and mildew are other common problems gardeners need to watch out for when growing dahlias. You can control petunia blight by removing any infected plant parts, but if this isn’t enough you may need to resort to spraying your dahlia with fungicide.

-If leaf miners are attacking your dahlias, apply an organic insecticide just before the leaves develop larvae–it won’t kill off the adult insects that have already infested your plants!

Dahlia Care During the Winter:

-If you grow dahlias in your garden, leave their foliage attached to the plant until it dies back naturally. Then cut it down and compost it over the winter.

-Alternatively, you can dry out your dahlia tubers by leaving them in a cool, dark place for 2 weeks after all the leaves have died back–if you do this, be sure not to damage or disturb their roots during this time! After 2 weeks, apply some Sulphur powder to prevent rotting and store them for next year in slightly damp sand or peat moss.

How to plant Dahlia?

-After all danger of frost has passed, carefully remove your dahlia seedlings from their pots and place them in the ground. Be sure to dig a hole that is wide enough for each plant to fit into comfortably–usually around 6-12″ deep.

-Spread some organic compost or manure into the soil at the bottom of each hole before planting your dahlias. This will help keep the roots cool and moist all summer long, even on hot days!

-Cover the roots with soil but leave the top of the tuber exposed so it can sprout new leaves. Then water well to settle everything down.

-Dahlias grow best when they are planted in groups of 3 or more plants so give them a little space–about 24″ should be fine, but it’s a good idea to check the specific requirements for your variety of dahlia to be sure.

-Space your plants 72″ apart if you’re growing them in rows or 3′ or more if you plan to plant them in between other plants, such as shrubs.

-Plant dahlias about 6″ deep if they are growing in containers or raised beds and up to 8″ deep if you’re transplanting seedlings.


-Dahlias are relatively easy to grow, but they do need a lot of sunlight to thrive. Other than that, all you really need to worry about is providing plenty of water when the plants are growing and putting in some compost before planting next year!

-Dahlia Tubers should be allowed to dry out completely after the leaves have died back in fall or winter then stored for next year wrapped in slightly damp peat moss or sand–be sure not to store them where they will freeze.

-After care is also important when taking care of each flower stem since it can get quite heavy after it has filled out with flowers so place your dahlia where it’ll be supported by tall stakes or trellises.

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