How to plant Dahlia Tubers:

Farm Grown Tubers: These will be a single tuber (rather than a clump of tubers). One tuber will grow one dahlia plant and by the end of the season will produce multiple tubers in a clump (which can in turn be divided).

Dahlia tubers come in all different shapes and sizes, and the size of a tuber is not an indication of how it will preform in the garden. The growth of the dahlia depends on several factors, including your garden conditions and vigor of the variety. You may see eyes or small sprouts, and/or fine white roots growing from the tuber – leave these in place and do not remove! If the sprout breaks off during handling that is fine - more sprouts will appear from that same eye.

Please store in a cool, dry place until you are ready to plant.

If you want to get a jump start on the season, tubers can be potted up a month before you plant them out. Keep them in your house, or somewhere warm and do not expose them to below freezing temperatures. Be sure to harden these off properly before you plant out!

Dahlia tubers should be planted outside after your last frost date and should not be planted out in unseasonably cold or wet weather. Wait until the soil has warmed up to plant them. Cold, wet weather and soil can cause the tubers to rot.

Dahlias require planting in a location that gets full sun (which means 6 or more hours of direct, uninterrupted sunlight per day). They like rich, well draining soil.

Dahlias can grow well in pots, provided the pot is large enough for the plant (minimum 16” square) with good drainage. Tubers may look small, but don’t be fooled – Dahlia plants are large and need space to grow. Crowding tubers will result in fewer blooms and stressed plants.

Once the soil has warmed up (soil temp of +15 Celsius) you can plant the tubers out.

Tubers should be planted 4 to 6” deep in rich soil, and laid on the soil horizontally, with any visible eyes pointing upwards. Plant each tuber a least 12” apart, so they have ample room to grow.

Remember to label you plants as you plant them! Cover over with soil, and do not water until you see green shoots appearing at the soil surface. Rain is fine but hold off on watering too much before they are showing signs of active growth. Once the dahlias are around 8 to 12” tall then they will need regular and deep watering! These are thirsty plants.

Dahlias benefit from ‘pinching’ which means once the plant reaches 8 to 12” tall, use sharp pruners or snips to cut off the top 3 to 4” of the plant – cut just above a set of leaves. This can seem counterproductive but will result in more stems from below the cut – which means more flowers to enjoy! Dahlias can be tall and require stalking, or a tomato cage to support them in Newfoundland winds. They also benefit from fertilizing throughout the season – be sure not to over fertilize and using ones high in Nitrogen will result in bushy growth but fewer flowers.

Dahlias can take anywhere from 12 to 16 weeks to bloom after planting, but once they begin blooming, they will keep blooming until the frost, as long as the flowers are cut or deadheaded.

They will not survive over winter if left in the ground, but Dahlia tubers can be dug up and saved each year at the end of the season.