How to Stake and Support Dahlias: Methods That Actually Work

Dahlias grow tall, produce heavy blooms, and will go over in wind without proper support. Once a plant goes down, you're dealing with broken stems, damaged flowers, and setbacks that cost you weeks of growing time.

Getting your support system in place before you need it is one of the simplest things you can do to protect a season's worth of work.

How Many Ways Are There to Stake Dahlias?

There are six to ten different methods depending on who you ask. The right one for you comes down to how many plants you're growing and how much time you want to spend on it. Here are the most practical options — from the simplest backyard setup through to the system we use at Highland Dahlias.

For Backyard and Cottage Garden Growers

Tomato Cages — Simple and Effective for Small Numbers

The cone-shaped wire frames from Bunnings or your local nursery do the job well for a handful of plants in a garden display. Push one over each plant early in the season and it'll have something to lean into as it grows taller. They're cheap, reusable, and require no tying.

Individual Stakes — Works, But Labour Intensive

A single stake driven beside each plant with the stem tied back as it grows is a tried and tested method. The limitation is time. A dozen plants, fine. A hundred plants, and you'll spend more time on stakes than on anything else in the garden.

For Larger Beds: Horizontal Flower Mesh

This is the method we use at Highland Dahlias, and it's the most efficient support system once you're growing at any real scale.

Instead of staking each plant individually, mesh is laid horizontally across the bed at two heights. Every stem in the bed grows up through the squares and is supported without any tying. One setup, the whole bed covered.

The specifics:

• Mesh size: 150mm × 150mm square mesh, available in metal or plastic
• Two layers: We use metal mesh on the bottom layer for durability and plastic on the top — plastic is easier on your hands when working through the beds
• First layer: Approximately 300mm above the ground
• Second layer: Approximately 900mm to 1 metre above the ground — adjust higher for more vigorous or taller varieties
• For very tall plants: Run a rope along the outside of the row at height to contain any outward lean

It takes more to set up initially, but once it's in place you're not spending time tying stems all season.

Fence and Wire Methods — Using What You Already Have

Two other approaches worth knowing about, particularly if you have existing structures to work with:

• Paling or boundary fence: Plant dahlias along a fence line and tie stems back to the palings as they grow. Works well for a dedicated row along the edge of a garden.
• Wire fence down the centre of the bed: Run a length of wire fencing lengthways through the middle of your bed and plant on both sides. Stems are tied back to the wire as they grow, giving support from both directions.

Practical Staking Checklist

• Get support structures in place early — before plants need them, not after
• For small gardens, tomato cages are the most time-efficient option
• For larger beds, horizontal mesh at two heights is the most effective system
• Use metal mesh for the bottom layer and plastic for the top
• First mesh layer at ~300mm, second at ~900mm–1m
• For very tall or vigorous varieties, add a rope along the outside of the row
• Never try to wrestle a metre-tall plant into a cage after the fact — you'll break stems

The support system you choose matters less than getting it right before the plants outgrow your ability to fix it. Once a dahlia goes over, the damage is done. Build your setup early and let the plant put its energy into flowers, not recovery.

Gerard Oldfield grows dahlias commercially at Highland Dahlias in the Southern Highlands of NSW. He is a regular contributor to the Dahlia Society of NSW and ACT monthly meetings.