Dahlia Growing Guide

Hi Flower Friends,

Thought I'd write a quick 'how to' for anyone planting dahlias for their first time.

Step one: Dream about all the different varieties and colors! Each tuber arrives individually bagged and labeled. They will look like a potato. You'll want to plant each tuber 12-24 inches apart. Plan how many you'll need for the spot you're envisioning. Click here to view all the tubers in our Dahlia Sale.

Step two: Once your tubers arrive you can plant them in a pot of soil to let them grow on in a greenhouse or indoors until it's safe to plant them outdoors. You'll want to plant them outdoors around your last frost date so that when the new green growth comes up it doesn't die back from the frost. I plant mine out at the beginning of May here in zone 8, a couple weeks before I put out my tomatoes or around the same time. 

Step three: Plant 3-4 inches deep with the 'eye' up. Plant in full sun in well draining soil. Full sun is necessary for strong tall stems and flowers to form. They do not need to be watered until you see green growth above the soil. Dahlias love slightly acidic to neutral soil with a ph of 6-7. Avoid using fertilizer with high nitrogen. Nitrogen promotes a lot of beautiful, strong stems and leafy green, but could prevent good flowering if you use it later in the season when the plant is wanting to make flowers. 

Too much water can rot the tuber so wait for that growth to pop up and then water deeply a couple times a week and enjoy summer blooms.

If you have the pests of the underground kind I would plant my tuber with mesh around it so the tuber doesn't get gobbled up. I've lost a lot of bulbs to the resident mole or gopher and need to take my own advice...something like this would work.

You'll also want to consider staking your dahlias with a branch or post once it reaches a certain height so that the stems do not snap and you get lots of long straight stems. 

We live in zone 8 so I do leave my tubers in the ground over winter, but if you're in a colder zone than I, you'll need to lift your tuber with a pitch fork after the first frost has wilted back the foliage. You'll be pleasantly surprised at the amount of dahlia babies your one tuber has made. Keep your clump of tubers together and store in a cool, dry, dark place to be divided and planted out again next spring. If you can leave them in the ground, cut back the stem to the ground after the first frost and you can mulch over it if you want to add an extra layer of protection from cold. 

Happy planting!

Laura