Dahlias thrive in well-draining soil rich in organic matter. Before planting, work compost or well-rotted manure into the soil along with some bone meal and an organic fertiliser to enhance its fertility. Ensure the planting area receives full sunlight, as dahlias need at least 6-8 hours of sunlight per day.

PREPARATION

Plant dahlia tubers in the spring, after the last frost date.

Depth and Spacing: Dig a hole about 10cm deep and place the tuber with the eye facing up. Space each tuber about 40cm apart, depending on the variety.

Now is a good time to stake your plants. As dahlias bloom they get top heavy and can fall over. Staking at the time of planting reduces the risk of damaging tubers.

No need to water at this point unless your soil is extremely dry. Dahlia tubers are prone to rot so it is best to wait until the plant has broken through the surface of the soil before watering.

PLANT

PROTECT &

MULCH

Protect young shoots from snails and slugs. You can opt to use an organic bait such as Protect-us or inspect your plants at dark and simply remove any snails or slugs.

When the dahlia has foliage you can then mulch to retain moisture loss in the soil. Mulching can also help prevent your tubers from rotting in the soil in hot weather.

PINCH

Want a bushier plant with more blooms? Pinch out the central growth tip when there are 3-4 sets of leaves. This will encourage lateral growth resulting in better stems for you to cut and enjoy.

If you want bigger blooms for a beautiful garden display then do nothing.

FERTILISE

In order for your plant to grow big beautiful blooms you need to feed it regularly. A strong healthy plant will produce beautiful blooms, be more resistant to pest and disease and stress less in periods of extreme weather.

If you have prepared your soil well you should not need to fertilise until about 6 weeks after planting.

There are many ways to feed your dahlias. On the farm we fertilise every 2 weeks with an added weak foliar feed in between.

You may opt for a slow release organic fertiliser applied at the base of the plant. This paired with a weak solution of fertiliser applied to the foliage on a weekly basis ensures plants are well supported. Foliar feeds are great as the plant can quickly take up nutrients it may be lacking that it may not be able to access from the soil.

What Fertiliser you ask?

In the early stages, to encourage plant growth, a fertiliser high in nitrogen will increase plant size and leafy growth.

When buds are beginning to form switch to a fertiliser high in potassium and phosphorus and low in nitrogen. If you continue with a high nitrogen fertiliser during flowering you may find your plant producing more leaf growth at the expense of the flowers.

Look for organic fertilisers specific for flowering plants that promote root growth and improve soil conditions.

As an example, a few applications of Potash during the flowering period will help promote big beautiful blooms and also help with tuber health.

Try a few different fertilisers and work out what works best in your garden.

Please note that Seasol is not a fertiliser but instead a plant tonic. It promotes health in plants but does not feed.

Watering is not required at the time of planting tubers unless the soil is extremely dry. Dahlia tubers are prone to rot so care is needed to not overwater in the early stages.

Once the plant has started growing then it’s best to water deeply twice a week in water retentive soil instead of a spray with the hose every other day. By doing this, it will encourage a deeper root system which results in a stronger plant that will cope better in prolonged heat and dry conditions.

If you have sandy soil then you may need to water more frequently as it will not retain the moisture.

Monitor your soil and plants and adjust your watering schedule as required. During wind and prolonged periods of heat you will need to increase watering.

WATERING

Dahlias do not continue to open much once cut so wait until the bloom is 3/4 to almost fully open before harvesting. Harvesting in the cool of the morning is best and place your cut flowers into a clean bucket of water.

See our Cut Flower Care Guide for more info on caring for your blooms and optimal vase life.

When harvesting you want to cut deep into the plant. Follow down the stem about 40cm and cut just above a set of leaves. This will encourage new growth and give you beautiful long stems. Be sure to pick flowers regularly as this will encourage more blooms.

Prefer to leave your blooms in the garden? Deadhead any spent blooms throughout the season as this will encourage the plant to continue flowering.

HARVEST

Tip: Always observe thorough hygiene methods when harvesting your dahlias. We use containers filled with methylated spirits to sterilise our snips when in the field. Snips are sterilised between each plant. This ensures that sap is not passed from one plant to another in order to avoid the spread of virus and disease.

In certain areas, the first decent frost will signal the end of the season for dahlias. The plants will begin to die back and tubers will ready themselves to be lifted and stored over winter.

You may choose to leave your dahlia tubers in the ground and overwinter them. This is fine as long as you don’t live in an area with freezing temperatures during winter and your soil does not get waterlogged.

If you live in an area that does not get frost and you want to initiate the plant into dormancy, begin to cut back the plant by a third each week. In 3-4 weeks you can lift your tuber clump to divide and store over winter.

As long as there are no signs of early rot, you can also leave your clump intact over winter and divide just before planting the following season.

END OF SEASON

STILL HAVE QUESTIONS?

Send us an email at hello@poppypusherco.com