Dahlia seeds - Mexican floral splendour from your own sowing
Dahlias make late summer shine: with single, semi-double or lush flowers, warm colours and a flowering period that often lasts until the first frost. If you sow dahlia seeds, you raise these summer flowers, originally from Mexico, yourself from the very beginning - from a small seedling to a flowering plant in a bed, container or cottage garden.
Read moreDahlias originally come from Mexico and are among the most impressive ornamental plants of summer. Over time, a few wild species gave rise to an enormous diversity of flower shapes, colours and growth heights. Alongside the familiar dahlia tubers, dahlia seeds are also interesting, especially for anyone who enjoys surprising flower colours, individual plants and growing them from seed.
Unlike true-to-type dahlia tubers, seeds do not always produce exactly identical plants. This is precisely what makes sowing so appealing: each plant may turn out slightly different in colour, shape, height or flower character. Lower-growing, single-flowered or mignon-type dahlias are especially well suited to growing from seed and often bring a lively, natural effect to the bed.
Dahlias love sunny, warm positions and nutrient-rich, well-drained soil. Waterlogging should be avoided, as the fleshy roots and later tubers are sensitive to too much moisture. In pots, containers and balcony boxes, more compact dahlias look especially beautiful, while taller forms in beds often need support.
- Dahlia seeds for colourful summer flowers in beds, containers, cottage gardens and cut flower plantings
- Exciting for anyone who wants to sow dahlias themselves and discover individual flower forms
- Ideal for sunny positions, a long flowering period and lively plantings from summer until the first frost
Whether as a colourful eye-catcher, a cut flower or a summer garden experiment - dahlias grown from seed bring diversity, warmth and surprise to the garden.
Sowing and growing dahlias from seed
Dahlias are easy to start from seed and, if sown early enough, can flower in their first year. Mid-March to mid-April is usually a good time to start them indoors. Sow the seeds about 0.5 to 1 cm deep in a fine, loose seed compost and keep them evenly moist but not wet.
At temperatures of around 20 to 22 °C, dahlia seeds often germinate within just 5 to 10 days. After emergence, the young plants should be kept as bright as possible and slightly cooler so that they grow strong and compact. Once the first true leaves have developed, the seedlings can be carefully pricked out into individual pots.
Before planting out, gradually acclimatise the young dahlias to sun, wind and changing temperatures. They should only be planted outdoors once there is no longer any risk of late frost. A sunny, warm position with nutrient-rich, humus-rich and well-drained soil provides the best conditions for a long flowering season.
Dahlias grown from seed usually form small tubers during their first season. Particularly beautiful or interesting plants can therefore be lifted in autumn, overwintered in frost-free conditions and planted out again the following spring.
Frequently asked questions about dahlia seeds
When should dahlia seeds be sown?
Mid-March to mid-April is usually a good time to start them indoors. This gives the young plants enough time to develop strongly before planting out, and they can often still flower in the same summer.
How deep should dahlia seeds be sown?
Sow the seeds about 0.5 to 1 cm deep and cover them lightly with fine compost. Even moisture is important, but waterlogging should be avoided.
What temperature do dahlia seeds need to germinate?
A germination temperature of around 20 to 22 °C is ideal. After emergence, the young plants can be kept slightly cooler, but they then need plenty of light.
How long do dahlia seeds take to germinate?
Under favourable conditions, the first seedlings often appear after around 5 to 10 days. Depending on the seed and growing conditions, germination may take a little longer.
Do dahlia seedlings need to be pricked out?
If several seeds were sown together, the young plants should be moved into individual small pots once the first true leaves have developed. This gives the roots and plants enough space for further growth.
When can dahlias be planted outdoors?
Dahlias are sensitive to frost and should only be planted outside permanently after the last late frosts. Before that, it is best to harden the young plants off gradually over several days.
Do dahlias grown from seed flower in the first year?
Yes. If started early enough and given good growing conditions, dahlias grown from seed can flower in their first summer.
Do dahlias grown from seed come true to type?
Not necessarily. Seed propagation produces genetically different plants. Especially with open-pollinated or highly bred dahlias, flower colour, flower shape, plant height and other characteristics can vary considerably.
Why do dahlias grown from seed look different?
Each seedling has a new combination of genetic traits. This diversity is exactly what makes sowing dahlias so exciting, as a seed mixture can produce very different flower shapes and colours.
Do dahlias grown from seed also form tubers?
Yes. Dahlia seedlings usually develop small root tubers during their first growing season. These can be lifted in autumn and overwintered in frost-free conditions.
Can you get a particularly beautiful dahlia from seed?
Yes. Especially interesting seedlings can be selected and then propagated vegetatively from their tubers or by cuttings. This preserves their individual characteristics.
Are dahlias winter hardy?
No. Dahlias do not tolerate hard frost. After the first frost, the tubers can be lifted, dried and stored in a cool, dark and frost-free place over winter.
What site do dahlias need?
Dahlias prefer a sunny, warm position with nutrient-rich, humus-rich and well-drained soil. Waterlogging should be avoided.
Are dahlias grown from seed suitable for containers?
Yes. Compact and low-growing seed-raised dahlias are particularly suitable for larger pots and containers. Plenty of sun, consistent watering and good drainage are important.
Which dahlias are particularly good for insects?
Single-flowered and open-centred dahlias are usually more valuable to pollinators than densely double forms because their pollen and nectar are easier for insects to reach.