As the last flush of dahlia blooms fade and the air begins to turn, it’s time for the tender ritual of closing the season. Whether you’re a backyard grower or running rows of cut flowers, knowing how to care for dahlias after blooming, store dahlia tubers, and collect dahlia seeds is a key part of sustainable, resilient flower farming.

At Femme Petale, we follow nature’s cues and trust the plants to tell us when they’re ready. Here’s how we approach post-season dahlia care with intention and ease.

When to Dig Up Dahlias (Or Not)

The best time to lift your dahlias is after the plants have gone down naturally—when they’ve stopped blooming or after the first signs of seasonal decline. This allows the tubers to store up all the energy they need to rest and regenerate. You can cut them down and wait a week or two before lifting them to encourage this process.

That said, in many parts of South Africa—especially here in Pretoria—our winters are mild enough to leave dahlias in the ground. Last season, we let our breeding patch overwinter in place, and even after a weekend of black frost, they bounced back beautifully. In fact, the in-ground tubers sprouted sooner and stronger than those we had lifted.

To overwinter dahlias in-ground:

Make sure your winter temps stay above freezing

Apply a thick layer of mulch for insulation

Ensure good drainage—excess water is a tuber’s worst enemy

How to Dig & Store Dahlia Tubers

If you choose to lift your tubers for winter storage, timing and technique matter. Here’s what we’ve learned through seasons of trial, error, and blooming success:

Step 1: Prep the Area

Remove all fencing, corralling, or netting that might block access. Cut back dahlia stems to about 10–15 cm above ground.

Step 2: Dig with Care

Using a pitchfork (not a spade—much gentler), start 30 cm away from the main stem. Loosen the soil in a wide circle and rock the fork gently back and forth until the tuber clump can be lifted.

Tip: Always lift by the base of the stem and never force soil off the tubers—you risk snapping off the necks.

Step 3: Wash & Dry

We wash our tubers thoroughly, then dry them in the sun on warm days until the outer skin is no longer tacky. This step is essential for avoiding rot in storage.

Dahlia Storage Methods That Work

We’ve experimented with a few different methods, and here’s what’s worked best:

1. Coarse Vermiculite in Crates

Gently nestle tubers in a breathable crate with dry vermiculite. Works well but requires extra care to keep moisture out.

2. Storing in Soil

Year two, we packed our clean, dry tubers in dry, sifted soil—and it was a game changer! Less work at planting time and excellent moisture regulation during winter. We have been doing this since.

Important: Always store in a cool, dry place with good airflow. Avoid plastic bags unless you’ve divided and individually wrapped each tuber with a label (we have not tried this method before, but believe it to be successful for some farmers).

Tips for Dividing & Labelling Dahlias

Labelling is the difference between a well-organized cutting bench and a field full of mixed surprises (we’ve had both!).

This season, we tagged tubers with picture labels while they were still blooming—a simple act that will save hours next year. When dividing your tubers in winter, make sure each has a visible eye (growth point), and label clearly before packing away.

If you’re not dividing, store the full clump and wait until early spring (August) to wake them up and take cuttings. In our field we do both. This ensures earlier blooms as well as later blooms, effectively extending our season as much as we can.

Save Your Own Dahlia Seeds

While dahlias grown from seed don’t replicate the parent (they’re genetically unique), seed saving is a beautiful way to create your own breeding lines and attract pollinators.

Two ways to collect seeds:

On the plant: Let the seed heads dry naturally. Once the petals fall away, you’ll find seeds tucked inside the cone.

Off the plant: Cut green seed pods (still on the stem) and place them upright in a jar or bucket in a warm, bright spot outdoors. In a week or two, the pods will ripen, and you can harvest the seeds into trays to fully dry.

We love the surprise and joy that comes from these bee-blessed babies—and this year, with more cross-pollination, we’re expecting a seed season like no other.

Final Thoughts from the Field

Caring for dahlias after the season ends is a quiet investment in next year’s beauty. Whether you’re digging, storing, or leaving them to rest in the soil, each step connects you to the full cycle of flower farming.

Here at Femme Petale, we honour the rhythm of the land and the hands that tend it. So as you tuck your dahlias in for winter, know you’re not just preserving plants—you’re growing legacy.

Looking for more seasonal flower care tips?

Join us at our next Sip and Sow event, our digging in with Dahlias in Spring or follow along on Instagram for behind-the-scenes stories from the field. And as always, feel free to share your own storage methods or seed stories with our growing Femme Petale community.