JEN’S TOP DAHLIA GROWING TIPS

Dahlias love full sun. The national recommendation is to plant tubers in the first week of November, after the last frost. I plant mine in October so they’re flowering for my farm tours in February.

Soil quality is important, so check pH levels. You can buy testing kits at major hardware stores. A pH level of 6.5 is ideal – add lime or liquid sulfur to adjust it. If you’re having trouble getting dahlias to grow, you can do a soil test through an independent lab, such as swep.com.au.

Dahlias love a rich, well-drained soil, so add lots of organic matter, like cow or sheep manure mixed with compost.

Pull up any dahlias that are showing signs of disease, and get rid of insect pests using predatory insects (available online) or an eco oil or fungicide. If your dahlias have gall (a bacterial disease), remove the whole plant and soil around it, so it doesn’t spread to other plants.

When my plants are 1m tall, I strip the bottom third of leaves to allow better airflow and prevent any fungal issues. Doing this also gives nasty bugs less space to spawn themselves.

If you’d like to grow your dahlias in containers, use pots that are no smaller than 30cm, and be prepared to provide your plants with a lot of love, including a monthly spray of foliar fertiliser or application of pellet fertiliser.

The common school of thought is to lift dahlia tubers each season after they have died back, but home gardeners can just leave them in the ground. To get the best out of them, dig them up every 2–3 years and divide the tubers.

Store tubers in a cool, dark place. I keep mine in fresh sawdust from the local sawmill, but vermiculite or potting mix is just as good. Check them monthly to make sure they’re not drying out, and give them a spritz of water if needed.