HOW TO GROW YOUR TUBERS
Dahlias are grown by tubers and can be planted in late August in Australia’s warmer climates and early October in the milder climate once the risk of frost is over.
The soil is best prepared with organic matter such as compost or sheep and cow manure. Be careful not to use horse manure as there may be pesticide residue that has been consumed in fodder by the horses that will affect the growth of your dahlias and may distort the blooms.
The tubers are planted 100mm, 4” below the soil with the eye or shoot facing upwards. Dahlias prefer well-drained soil. If grown in heavy loam soil with a heavy rainfall, you may need to lift and store early after the first frost to avoid the tubers rotting. A good sunny position with afternoon shade is the ideal location. The plant will require to be supported as it grows by means of a stake or trellis. Some growers prefer to let them grow up through 6”, 150mm square netting set at the height of 300mm and a second height at 600mm.