Dahlia Growing Tips
Dahlia Growing Tips
We moved to Braidwood a few years ago, and shortly afterwards I was gifted a few mystery dahlia tubers. We basically just planted them in the ground and were surprised by the results. Since then, I've been reading and watching everything out there about dahlias.. and our dahlia patches have grown year on year. Here are some tips I’ve collected along the way.
Storing until Planting
When your tubers arrive, store them in a cool, dry place if it’s a while before you’ll be ready to plant (they will arrive in saw dust). Check when you’re able to pop them in the ground for your climate zone. For us, in our cool climate, we wait until after the last frost.
Soil Preparation
Once you have chosen a sunny spot with well-drained soil for your dahlia patch, it’s important to check the soil’s condition and improve your soil as required. We have a few cows, so it’s easy for us to add well composted cow manure to our dahlia beds. I also add our own compost, plus Seamungus, lime and multi grow. I top the beds with sugar cane or pea straw mulch. There are crops you can plant to suppress weeds and improve the soil in between the growing months – I haven’t experimented in this space yet. Everyone’s soil will be different. I had grown a few dahlias initially to test my location, and then kept planting nearby my test patch. I sent soil away for testing in each area of our farm we planned to grow certain things for some expert advice on what to add in which location. Depending on how many dahlias you plan to grow, it could be worth testing your soil and adjusting your soil conditions to suit. Our soil beds are built up to a good 25cm or so, with lovely loose soil containing good organic matter.
Planting
To plant dahlia tubers (also called bulbs), wait until the danger of frost has passed and the soil has warmed, this is usually in late spring. Dig a hole about 10-15cm deep and lay the tuber horizontally with the "eye" (a small bump where sprouts emerge) facing up. You want this top part of the tuber to be sitting about 8cm below the ground. Space tubers about 30-40cm apart to allow room for growth and cover with soil. Label your dahlias well if you are planning to divide or pass on tubers or keep track of your own dahlia collection. I have quite a few mystery tubers this season as I decided permanent marker on bamboo forks would be a great system for labelling some of my dahlias – turns out, no – you need to use a garden marker on plastic markers or gardeners tape around the stem and you need to check your labelling system is holding up well.
Watering & Staking
Do not water your dahlia bulbs heavily until they start sprouting and reach around 10cm in height, as excess moisture can cause rot. Once the plant is growing, you’ll need to water regularly. We set up a drip watering system for our dahlias – we adjust this depending on the weather, but generally we have our drip system on initially twice a day, for 10 minutes each time. We check the effectiveness of this and adjust as needed. As the weather warms up, we have increased this to three times a day. We have also switched our watering system off during period of good rainfall to save overwatering. Prepare stakes or a system for supporting your dahlias as they grow, quickly and tall. There are a lot
Follow the Dahlia Community
There is so much information out there – many You Tube instructional videos and dahlia blogs that have many and different answers to your dahlia growing questions. I have enjoyed learning as I go and trialling different approaches to storing, dividing and growing dahlias
Enjoy your Flowers
You may like to experiment with clipping, or pinching, out the centre stems of your dahlias to encourage more flowers. The best time to do this is when your dahlia plant is about 40cm tall with three to four sets of leaves. Last year we enjoyed dahlia flowers from December through to early April. Regularly picking the flowers helps the plants to keep on blooming, so cut them and enjoy them and cut back any flower heads that you didn't manage to pick while at their best.