Growing Dahlias
A beginner's guide from Avlon Farm Flowers
Dahlias are one of the most rewarding flowers you can grow, producing an incredible display of colour, shape and texture from summer right through to autumn. Whether you're growing a few plants in your garden or establishing your very own cut flower patch, dahlias are surprisingly easy to grow with a little care and attention.
At Avlon Farm Flowers, we love dahlias for their beautiful blooms, extraordinary variety and ability to produce flowers for months on end.
We've put together this simple guide to help you get the most out of your dahlia tubers.
1. Choosing the Perfect Spot
Dahlias thrive in a sunny position with fertile, well-drained soil.
Sunlight: Choose a location receiving at least half a day of sunshine. While dahlias enjoy sunlight, some protection from the intense afternoon sun can be beneficial during our hot Central West summers.
Soil: Good drainage is essential. Dahlias dislike sitting in wet, waterlogged soil, which can cause their tubers to rot. Most garden soils are suitable, provided excess water can drain away.
Soil preparation: Before planting, improve your soil with organic matter and a moderate amount of general-purpose fertiliser. Preparing your garden bed a week or two before planting will give your dahlias a great start.
Watering: Dahlias grow best with a consistent supply of moisture, particularly during the warmer months. A drip irrigation system can make watering easier and more efficient.
2. When to Plant Your Dahlia Tubers
In the Central West of NSW, dahlia tubers are generally planted from mid-October through to November, once the risk of damaging frosts has passed and the soil has started to warm.
Planting can continue into December, depending on seasonal conditions.
There's no need to rush! Dahlias establish well in warm soil and often produce their most spectacular flowers towards the end of summer and into autumn.
Our tip: Be patient with planting, particularly if we're experiencing a cold or wet spring. Warm, well-drained soil provides a much better start than planting too early.
3. How to Plant Dahlia Tubers
Planting your tubers is simple, and a little preparation will help them establish successfully.
Prepare your planting hole. Dig a hole approximately 10–15 cm deep.
Position your tuber. Lay the tuber horizontally, with the eye (the small growing point near the neck) facing upwards.
Allow enough space. Position tubers approximately 40–60 cm apart to provide room for growth and airflow.
Install support. Place a sturdy stake beside the tuber at planting time. Installing stakes early avoids accidentally damaging the tuber or roots later.
Cover with soil. Gently backfill the hole, taking care not to damage the growing eye.
Water according to conditions. If the soil is already moist, there's usually no need to water immediately. In warm, dry conditions, a little water may be necessary.
Important: Avoid keeping freshly planted, unsprouted tubers excessively wet. Too much moisture before active growth begins can lead to rot.
4. Caring for Your Growing Dahlias
Once your dahlias begin to emerge, you'll be amazed at how quickly they grow!
Protect new shoots
Tender young dahlia shoots are particularly attractive to slugs and snails. Keep an eye on emerging growth and protect your plants from pests, especially during their first few weeks.
Mulching
As the weather warms, apply a layer of organic mulch around your plants. Mulch helps retain soil moisture, keeps roots cooler during summer and reduces weed competition.
Feeding
Dahlias are vigorous growers and benefit from adequate nutrients. A balanced, general-purpose fertiliser during early growth can help establish strong, healthy plants.
Avoid excessive fertilising, and always follow the manufacturer's recommended application rates.
Supporting your plants
Many dahlia varieties grow between 90 cm and 180 cm tall, with some growing even taller.
As plants develop, loosely secure their stems to sturdy stakes or other suitable supports. This helps prevent damage from strong winds and the weight of large flowers.
5. Pinching Dahlias for More Flowers
One of the simplest ways to encourage a fuller, bushier dahlia plant is through a technique called pinching or stopping.
When your plant has developed approximately four pairs of leaves, remove the central growing tip just above a pair of leaves.
This encourages the plant to produce additional side shoots rather than continuing to grow as a single main stem.
The result is a bushier plant with more flowering stems and potentially more blooms throughout the season.
Our tip: It might feel strange cutting the top off a perfectly healthy young plant, but pinching is a wonderful way to encourage branching and increase flower production!
6. Encouraging Beautiful Blooms
As your dahlias mature, flower buds will begin developing at the ends of their stems.
Dahlias commonly produce a central bud surrounded by smaller side buds.
If you're growing dahlias for cut flowers, you can remove the smaller side buds to encourage a larger central bloom with a stronger, more usable stem. This technique is known as disbudding.
Disbudding is optional, particularly if you're growing dahlias purely for garden enjoyment.
Keep picking!
Regular harvesting is one of the best ways to encourage dahlias to continue flowering.
Cut flowers for your home, give bunches to friends or remove blooms as they begin to fade.
Removing spent flowers helps keep the plant producing new blooms rather than directing energy into seed development.
With regular attention, your dahlias can provide flowers for months.
7. Watering During Summer
Dahlias enjoy consistent moisture during active growth, especially when temperatures rise.
During the hot, dry summers we often experience in the Central West, regular watering is important for maintaining healthy plants and good flower production.
Aim to water deeply enough to reach the root zone rather than applying frequent, shallow watering.
Try to avoid prolonged waterlogging and adjust your watering schedule according to rainfall, soil type and temperature.
Mulching and drip irrigation are excellent ways to help maintain even soil moisture.
8. What Happens at the End of the Season?
Dahlias continue flowering into autumn until cooler temperatures and frost bring their growing season to an end.
Once the foliage has died back, the plant enters dormancy, with its tubers resting beneath the soil until warmer conditions return.
Do I need to dig up my tubers?
Not necessarily!
Dahlia tubers can remain in the ground over winter, provided the soil drains well and they are protected from prolonged excessive moisture.
Alternatively, tubers can be lifted, divided and stored for replanting.
Regular division helps prevent overcrowding, maintain healthy plants and provides an opportunity to increase your collection.
If you choose to leave your dahlias in the ground, mark their location so you know where to find them in spring.
Our tip: There's no need to rush into lifting and dividing tubers as soon as the flowering season finishes. Many growers prefer to wait until the growing eyes are easier to identify, making division simpler.
9. A Few Extra Tips for Dahlia Success
Start with healthy tubers. Quality planting material gives your dahlias the best chance of success.
Don't overwater newly planted tubers. Wait for active growth and adjust watering to soil conditions.
Provide support early. Dahlia stems can become heavy and vulnerable to wind damage.
Keep picking your flowers. Regular harvesting encourages continued flowering.
Label your varieties. It's surprisingly easy to forget which dahlia is planted where!
Enjoy the process. Every growing season is different, and part of the fun is discovering which varieties thrive in your garden.
Happy Dahlia Growing!
Whether this is your first season growing dahlias or you're adding new varieties to an established collection, we hope your tubers bring you months of beautiful blooms.
Dahlias are wonderfully rewarding flowers, and with a little care, they'll keep giving season after season.
Happy growing!
Avlon Farm Flowers
Grown with love in the Central West of NSW