Dahlia FAQ's
Frequently asked questions for dahlia tubers
How do you plant dahlias?
Dahlia tubers should be potted up into 15-20cm diameter pots with multipurpose compost between late February and early June. The earlier in spring you can plant them, the sooner they will develop and start flowering in summer. The tubers should be su
When can I order dahlias?
Dahlias are available to order between late December and late May. They are shipped from mid/late February onwards in time for spring planting. You can browse our range of dahlias at any time of year on our website. When listed as out of season you c
When should dahlias be watered?
Dahlia tubers should be watered straight after they're potted, and again whenever the compost in the pot feels dry below around 3-5cm from the surface, even if the tuber hasn't yet sprouted. If the compost is allowed to dry out for a prolonged period
When should you plant dahlias?
Dahlias can be planted between late February and early June. For most reliable results, they should be potted up into 15-20cm pots and grown on until the plant is around 20-30cm tall before transferring into borders. This applies even if there is no
Can dahlias grow in pots?
Dahlias can be grown in patio containers, each tuber should be planted in a pot which measures at least 30cm in diameter. Planting more than one dahlia in a pot can be too much, they will compete for space and nutrients which will affect their perfor
What do dahlia tubers look like?
Dahlia tubers have between one and several 'fingers' attached to the crown. The tubers should be firm and dry, it is not usually a problem if the tubers appear slightly shrivelled providing they are not soft. There is usually, but not always, a small
Should potted dahlias be kept dry if they haven't yet sprouted?
Newly potted dormant dahlias should be watered whenever the soil feels dry below around 3-5cm from the surface, even if they haven't sprouted yet. If you do not water them and the soil is dry for a prolonged period, the tuber can also eventually dry
How long do dahlias take to sprout?
Typically it takes between 3-7 weeks for a dahlia tuber to sprout. How long it takes a dahlia to come out for dormancy depends on how early in the season it is planted, planting depth and temperatures. Potting in early spring may mean that the tubers
Should dahlia tubers have buds/eyes when they arrive?
When supplied in early spring, dahlia tubers may still be completely dormant and may not have any visible buds/eyes yet. Buds/eyes typically start to appear by around April. Dahlias supplied during April and early May are more likely to have visible
How do I protect dahlias from slugs?
There are various methods that gardeners use for protecting dahlias from slugs and snails:. - Start dahlia tubers in small temporary pots on a raised surface, this will allow dahlias to develop healthy growth and won't attract the attention of slugs.
When are potted dahlias are ready to plant out?
Dahlias which have been potted and grown on should only be planted out into borders when all risk of frost has passed in your area, which is usually around early May. It is important not to transfer dahlias before they are ready - if the soil falls f
How do you look after dahlias?
For best results, plant your dahlia tuber into a small temporary pot between late February and early May and allow it to grow on in bright, frost free conditions for a couple of months until it is around 20-30cm tall. After risk of frost has passed (
How deep do I plant dahlia tubers?
Plant dahlia tubers shallowly in the soil with the stump of last year’s stem level or slightly exposed from the soil surface. Ensure the tubers are completely submerged below the soil surface to prevent them from drying out. Avoid planting too deep a
Do dahlias grow back every year?
Dahlias are half-hardy perennials which means they can grow back every year but they do need winter protection. In areas where frosts are likely over winter, or with heavier soil types which can become waterlogged over winter, it’s necessary to lift
What do you do when dahlias have finished flowering?
Dahlias usually continue flowering until the first frost. If they have stopped flowering before the first frost, anytime between September and December the tuber can be lifted from the soil. If they are still flowering well through autumn, you can le
How should I store dahlia tubers if I can’t plant them straight away?
Dahlias are freshest and most viable when supplied and it is recommended to pot them up within a few weeks of delivery for best results, and to give them as much time as possible to develop. If you cannot plant them soon after delivery, unpack the da
What do you do if some of the dahlia tubers are broken?
Dahlias often have some broken tubers, they will still grow providing there is at least one good-sized tuber firmly intact. Partially broken tubers do not need to be removed - often they are attached enough to still support the plant, or the partiall
Do dahlias flower in the first year?
Dahlias flower reliably in their first year providing the growing conditions are right for them and they are planted at the correct time. Dahlias planted in early spring usually start flowering by around mid-late July. Dahlias which are potted in lat
Why has my dahlia not started flowering?
Dahlias typically flower from mid summer into autumn, and exactly when they will start to flower depends on many factors including the variety, temperatures, planting time, soil conditions and how much sun they get. Varieties with smaller flowers suc
How do I deadhead dahlias?
You should deadhead dahlias regularly because this will encourage more blooms to be produced over a longer period. To do so, simply snip off faded flowers at the base of each individual flower stem where it intersects with a leaf or the main stem. Fa
When do dahlias flower?
Dahlias typically flower between around July and October, often continuing later in autumn if there’s no frost. They can be encouraged to start flowering earlier by planting early in spring in a heated greenhouse or indoors. They continue flowering t
Can I leave dahlias in the ground over winter?
Dahlias are best lifted in late autumn, cleaned, dried and stored in a frost free location to protect them from freezing winter weather. In very mild regions where winter temperatures rarely drop below 1C and the soil is well drained, they often surv
How long do dahlias flower for?
Dahlias flower continuously throughout summer and autumn until the first frost if they are regularly deadheaded and the growing conditions/temperatures are favourable. The earlier they are potted in spring, the earlier they can develop enough to begi
Do dahlias need feeding?
Dahlias often produce better growth and more flowers if they are fed fortnightly throughout the growing season, especially if grown in pots where the soil can quickly become depleted of nutrients through the growing season. However, they will still f
How many flowers grow from one dahlia tuber?
One dahlia tuber grows into a bushy plant with multiple flowers which are produced continuously throughout summer and autumn. The number of blooms on a dahlia plant varies depending on the variety. Large-flowered varieties may produce fewer but large
How do you store dahlia tubers over winter?
Lift dahlia tubers in autumn between late September and mid November. You can wait until the first frost if they are still flowering well in early autumn. Any soil should be carefully removed from around the tubers. Allow the tubers to dry off in a w
Why are the leaves on my dahlias yellow?
Towards late autumn your Dahlias will start to die back in preparation for winter dormancy. The leaves and stems will naturally begin to turn yellow and can be trimmed away when you lift the tubers for overwintering. However if you notice the leaves
Where is the best place to plant dahlias?
Dahlias can be planted into large patio containers or into borders in a sunny or partially shaded position with free-draining soil. Avoid areas with very dry or compacted soil, or planting among competing plants such as in grass, very close to hedges
How can I get my dahlias to flower earlier?
The only way to bring Dahlias into flower sooner is to plant them earlier in the season. To encourage speedy development, start them off in pots in a heated greenhouse in late February/ early March. They will reach maturity earlier in the summer and
When should dahlias be lifted and stored?
To protect your dahlia tubers from freezing winter conditions, it is best to lift and store your dahlia tubers in autumn. Often dahlias are flowering most prolifically in early-mid autumn, so you can wait until the first frost to lift your dahlias. I