Growing Dahlias

Intro

Growing dahlias is so rewarding.

Whether you’re planting for the first time or have been growing for years, these are a few simple guidelines that have worked well for me here on the South Shore in Massachusetts.

Planting

Plant your dahlia tubers after the danger of frost has passed and the soil has warmed to 55 degrees.

Choose a spot with full sun (at least 6–8 hours per day).

Plant tubers about 4–6 inches deep, laying them horizontally, with the eye facing up if visible. Space plants about 12–18 inches apart.

Watering

After planting, water lightly. Do not water again until after they push up green growth. Too much water = rotted tubers.

Once growth begins, water regularly, especially during dry periods. Dahlias prefer consistent moisture but do not like sitting in soggy soil.

Pinching

When plants reach about 10–12 inches tall, you can pinch the center stem. Count from the soil up 3 or 4 leaf sets and pinch out anything above.

By pinching out the growing tip you are encouraging branching versus vertical height and results in more blooms over the season.

Staking

Many dahlias benefit from support.

It’s best to stake early, at planting time, it is very easy to spear directly through your tuber if you stake after you have covered your tuber. You can use stakes, cages, or netting depending on your setup.

Cutting Flowers

Cut flowers regularly to encourage continued blooming.

Cut deep. Think the length from your finger tip to your elbow. Cutting short stems signals the plant to continue giving you short stems. It will look like you are cutting too much, trust me, you are not. You will get long stems and the plant will continue to give you long stems. You can also think of it as providing the plant with airflow if that makes it easier.

Cut above a leaf set.

Harvest blooms when they are fully open. Some growers say that the flowers do not continue to open once cut. I have found that some do. You may also like the texture that buds provide to your arrangements and bouquets. Play and have fun with the varying stages! Morning or evening is the best time to cut. Place in cool, clean water out of direct sunlight.

End of Season

After the first frost, foliage will begin to die back.

At that point, you can dig and store tubers or treat them as annuals depending on your growing preferences and climate.

Thank you so much for supporting my small flower farm.
I hope these dahlias bring beauty and joy to your garden all season long!