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PLANTING DAHLIAS ADVICE

Here's a little advice before planting, its good practice to soak your tubers in a bucket of tepid water for an hour so they can fully rehydrate after they have been taken out of their winter storage. Starting off your dahlia tubers in plant pots will also encourage them to develop more quickly, so they’re likely to start flowering earlier ahead of your neighbours!.

Once all the risk of frost has past, April/May, here in the UK, find a sunny position with fertile, moist but well-drained soil. Alternatively, you can start them off in indoors in pots in March/April and keep them in a frost-free location like a greenhouse or outhouse before transferring them outside after the last frosts.

 

Position the dahlia tubers just below the soil surface, covering your tubers with approx. 3cm (1-2″) of soil. Allow approx. 30cm (12″) spacing between each tuber. (The spacing may vary depending on the final size of the variety.) Ensure to plant your tubers the right way up by locating the old stem – this is the top of the dahlia.

When planting in the garden, mulch over with compost or straw, you can also use leaves to protect them from the risk of any late frost, douse the hole with a watering can full of water and cane as you plant to help protect them from falling in strong winds.

Important Benton end flower farm Hint:
“After a few weeks and your dahlias start to produce shoots, you may need to start protecting the new dahlia shoots from those pesky slugs and snails by using organic slug pellets or you could collect up the nocturnal pests at night! or what we use is raw SHEEPS WOOL, in May, most sheep farmers will be sheering so by asking the local farmer for a bag of his wool, its cheap and perfect timing for your dahlias! All we use is sheets wool, we wrap it around the dahlia plant and that works very well, the bonus is you can also use this for Hosta's too! Sheets wool contains LANOLIN ands this is why slugs and snails will not cross the wool. 

And do not worry about putting wool on your garden (colour of wool does not matter) as it is natural and will break down into the earth.

PLANTING DAHLIAS IN POTS

 

Dahlias can spread quite vast so we advise planting 1 x dahlia tuber in a 2 to 3 litre pot or 30cm (12″) in diameter and fill with a good-quality, multi-purpose compost. Ensure sure the pot has good drainage because the tubers will rot if left to sit in water. If the pot only has 1 or 2 holes, you can add more with a drill to prevent the tuber from rotting. Adding good draining elements like bark to the base of the pot will help with drainage.

Use a slow-release fertiliser to promote strong growth and stake when planting.

Lay your tuber flat in the container with the eye or sprout, if there is one, facing upwards. Plant with the eye just above the soil surface.

Benton End Flower Farm tip:
Dahlias will flower throughout the summer/autumn and so keep dead-heading them, this will prolong their flowering period.

CARING FOR DAHLIAS

  • You can feed your Dahlias with a diluted Tomato feed every 2 weeks or as we do, we feed with a good slow release fertiliser.

  • Support Dahlias with canes on planting and tie in as growth develops.

  • When your Dahlias reach about 30cm in height, pinch out the growing tips with your thumb and forefinger or use a sharp knife. This will encourage branching.

  • Water once a week with a good amount not just a little sprinkle.

  • Deadhead flowers as they fade.

OVERWINTERING:

  • Once the first frosts have blackened the foliage, cut the plants back to about an inch from the ground.

  • In well-drained soils or in mild parts of the country, you can keep your dahlias planted in the ground over winter, mulch them over deeply with 6-12cm of compost to protect them from frost. In colder climates or heavier soils, lift and store your tubers over winter.

  • Replant the following spring. 

  • If you are lifting and storing your dahlias for winter, ensure to clean off any soil and dry them before storing in a cardboard box filled with wood shavings (you can purchase this from any pet shop). Keep the tubers in a cool, dry spot like a garage or shed.

  • If in pots, stop watering at the end of summer and bring them indoors for winter to protect against frost. Place back outside once the danger of winter frosts has passed. 

LIFTING AND STORING OVER WINTER:

  • Cut back foliage and carefully lift the tubers out of the soil.

  • Allow the tubers to dry off naturally and then clean away any soil. 

  • Trim the stems back to 1-2 inches and cut off any fine roots it won't hurt them.

  • Make sure the tubers are completely dry before storing them into cardboard boxes. Pack in sawdust or wood shavings.

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