Climate & Timing

In temperate regions like Mudgee, dahlias are planted in spring once the danger of frost has passed — usually around mid October. Dahlias thrive in warm soil and sunny conditions. Through summer they’ll reward you with abundant blooms, and with the right care, you can enjoy flowers right through until the first frosts of autumn.

Choosing the Right Spot

Dahlias love the sun so choose a position with at least 6 hours of sunlight per day. Good airflow helps prevent mildew and pests, but avoid spots that are too exposed to strong winds. Here are some location options to consider.

~ Plant them in garden beds or rows for a flower-farm look.

~ Grow in large pots (at least 40cm wide and deep).

~ Tuck them into mixed garden beds alongside herbs or veggies, they’ll happily blend in, as long as they get enough sun.

Preparing the Soil

Healthy soil makes happy dahlias. Work compost or well-rotted manure (cow, sheep, chicken) into the soil before planting. A handful of blood and bone or a slow-release fertiliser can also help get them started. Avoid freshly manured soil, it’s too “hot” and may burn the tuber.

Good drainage is essential. Dahlias don’t like sitting in waterlogged soil, so raised beds or adding organic matter to lighten heavy clay is worth the effort.

Planting Your Tuber

1. Dig a hole about 10–15cm deep.

2. Lay the tuber flat with the “eye” (growing bud) facing up. If you can’t see an eye yet, don’t worry…plant anyway, and it will sprout when it’s ready.

3. Cover with soil and water lightly.

4. Space plants about 50cm apart if planting more than one.

Tip ~ Don’t overwater before the shoots appear, tubers can rot if they stay too wet.

Caring for Your Dahlia

~ Watering – Once shoots are established, water deeply 2–3 times a week. In hot Mudgee summers, they’ll appreciate consistent moisture. Mulch helps retain water and keeps soil cool.

~ Fertilising – Early growth loves a little nitrogen for strong leaves and stems. Once buds form, switch to a potash-rich feed to encourage flowering. Too much nitrogen = lots of greenery, not many flowers.

~ Pinching – When plants are about 30cm tall, pinch out the growing tip. This encourages bushier growth and more flowering stems.

~ Staking – Dahlias can grow tall and top-heavy. Add stakes or flower netting early, before plants get too big, to keep stems supported.

Pest Watch

Dahlias can attract aphids, caterpillars, and sometimes mildew in humid weather. Check your plants regularly. Encourage beneficial insects like ladybugs, or use gentle organic sprays (like neem oil) if needed. Prevention is easier than cure.

Harvesting Blooms

The more you cut, the more they bloom! Harvest in the cool of the morning or evening when flowers are hydrated. Cut stems just as blooms open, using clean snips, and place straight into water. Removing spent blooms (deadheading) also keeps plants flowering longer.

Winter Care

In temperate climates, frosts will cut your dahlias back in late autumn. Once the foliage has blackened, cut stems to the ground. With a good layer of mulch, many tubers can be left in the ground to reshoot the following spring. For extra insurance, you can lift tubers, store them in a cool, dry place, and replant next season.

Watch the Planting Video

Still unsure? Watch my step-by-step video on planting your dahlia tuber, it’s the simplest way to see exactly what to do.

Dahlias may seem a little fussy at first, but once you get the hang of them, they’re pure magic. From a single tuber, you’ll have armfuls of flowers all summer long. Each season teaches you something new, and before long you’ll be hooked on their variety and beauty.

If you have questions or would like a little extra guidance, my Instagram DMs @posieclub_ are always open. I’d love to see your dahlias blooming and cheer you on as your garden grows.

With love, Candice

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