Dahlia Corner

As Dahlias are very tender when they are first shooting, it is best to start them off in boxes or pots with a good multi-purpose compost that retains moisture but does not stay wet in a warm environment such as a greenhouse. To aid the drainage add either Perlite or Vermiculite to the mix.

When the frosts have finished it is wise to start to harden them off outside before planting them in your borders. When planting put a stake in the ground so you can tie them up for support. They do like a very sunny part of the garden.

At the end of the season when the first frosts have turned the leaves a bit black, cut the foliage down to about 3 cm from the ground then lift the tuber, remove most of the soil leaving a small amount behind for insulation, turn them upside down to drain then store them in boxes in a frost free environment during the winter.

It’s that time of year for all you Dahlia lovers. You need to think about planting tubers in pots or trays in a warm greenhouse that is frost free.

Use a good quality multi-purpose compost, you should see the first shoots coming in 3 – 4 weeks. Leave a little bit of the tops of the tubers showing, do not over-water just keep the compost damp. This will aid the “waking up” process.

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Once the shoots are about 4 – 5 inches high you should be able to take cuttings to increase your stock.


The key is to dip the end in a good rooting compound before potting them up.

As you can see Dahlias will grow quite happily in raised beds or even in containers or large pots. Keep them watered in very hot weather and once a week give the roots a good watering.

Dahlias are a sun loving plant and need well drained soil. In the nursery our beds are filled with a nitrogen rich soil which the Dahlias seem to thrive on.

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If you have a heavy clay soil, when planting put some grit in the bottom of the hole to aid drainage.


Taking cuttings

It’s that time of year again when you take cuttings from your Dahlia tubers to increase your stock of your favourite varieties.

Earlier I gave you a rough idea of what needs to be done when you take cuttings. I can now give you a much more detailed guide.

Firstly, you need to make sure that the shoots that you are using from the tuber are strong enough to take the cutting process.

As you can see there are lots of healthy shoots to choose from. The one in the foreground is the strongest.


They need to be about 5 to 6 inches in height with at least 3 sets of leaves.

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When you take the cutting use a sharp small knife.  As you cut make sure you take a sliver of the tuber as this will aid the rooting process.

As you can see I have just taken the smallest of pieces of the tuber thus preventing any further damage to the main crown.

If possible choose a shoot away from the main crown. There will be many shoots from the actual tubers themselves.

Once you have taken the cutting, place the end in a little water to dampen the end before dipping in good quality rooting compound.

Do not shake too much off the end as the more there is the better the chances of success.

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Finally place the cutting in a 6 inch pot filled with good quality multi-purpose potting compost, water then place in a warm shady place in a green house or on a windowsill but not in direct sunlight until you see new growth at the top of the cutting.

When you see roots protruding from the bottom of the pot it is then time to re-pot them in larger pots until ready to plant out in your borders.

The cutting shown is from Arabian Night, a very prolific plant giving beautiful Dark Red blooms about 4 – 5 inches in size.

They grow to about 5ft tall and are of the Decorative variety.

Plants will be available to buy from the Hamblin Plant Nursery in late May.

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Once the plant has become established in its pot, by late May to early June, once the frosts have gone, you can plant them in their final position.


During the growing season they will make their own tubers which will need to be lifted in the winter to prevent them from rotting.


The tuber shown is one that I grew from a cutting taken in April 2020.

You can take cuttings from any variety of Dahlia. The process is still the same.