Overwintered Dahlias- The Summary
I harvested the first blooms from our over-wintered dahlias this week! They are beautiful and I’m slightly addicted to dahlias even more than usual right now!
This blog serves to educate but also as a record of trials and experiments so I want to record the process here for you.
I guess it technically begins last Spring. I planted 2 rows of Blizzard tubers. I was seriously thinking about overwintering so I allowed them a bit more space. I planted 3 rows of 45 tubers in a 36” bed, 45’ long. So glad I did— they are huge this Spring.
The beds bloomed beautifully last year. In the Fall, I cut them down to the ground and tarped over them. This planting area doesn’t have raised beds and the beds aren’t raised too much above the ground level. (One of the 3 beds rotted over the winter- it was on the edge of the tarp and I think too much water got in.)
I pulled the tarps off in early March. I should have pulled off in mid February with the warm winter we had. This is a note to self for next year— pay attention to climate conditions and take tarp off earlier. Also I plan to monitor soil temps in this area next winter. When I see them hitting 60- I’ll definitely get the tarp off.
The plants were sprouted some beneath the tarp when it came off. This is a huge issue but it does make it easier if you need to weed, fertilize, add compost if the plants aren’t sprouted yet.
The plants began to grow but were checked about 10 days later by a frost. This is pretty normal for over-wintering dahlias in our climate. We get random harsh Spring frosts. You can protect your plants if you like but they will resprout.
They will resprout within 2 weeks usually. Fortunately we didn’t have another frost hard enough to take them down. It is a bit warmer near the ground like that.
So they were off to see how fast they could bloom. I pinched the last week of April. They could have used it about a week earlier but we had a very rainy spring and it was hard to find a dry window to do the pinch. We missed a few stems so some of the first blooms have broomstick handles.
We also fertilized at this point. Next year, we’ll lay it down right after we pull the tarp off. They can definitely use it when they get started.
We got them mulched in early May. They don’t look like they’ve grown much here b/c they are recovering from the pinch at this point.
I discovered the first bud the next week. I also documented some flooding and drainage issues in the row next door. This was the row that rotted over the winter. We corrected this row before planting- we added lots of compost and gypsum to help with the drainage. We mulched it after planting to keep the weeds down.
In the 3rd week of May we got our netting up- about 2 weeks later than we should have but fortunately not too late.
We also began the bagging process.
And about a week later— Blooms!! We were cutting the first 2, followed by a bucket more a few days later!
I’ve loved this process! I’ll definitely be doing more of it in years to come. It hasn’t been without it’s challenges. Bug control is a lot more important in early season- so many more things you have to watch out for. Just this morning we had to throw out a 1/3 of our harvest because they had so many thrips on them. We’ll keep spraying and doing what we can to address it. But I would say the good outweighs the bad!