2023/24 was my first year growing dahlias and I took a very laissez faire approach - I needed the experience to be low stress and less about the outcome and more about enjoying the process and learning something completely new.
All in all I was pretty happy with how it went but there are a few things I would do differently for 2024/25.
My patch wasn't ready when it was time to plant (Labour Weekend here in the Waikato or after the risk of frost has passed) so I planted my tubers in pots on the back deck. This was great because it allowed me to take plenty of cuttings.
Use individual pots for your dahlia tubers
I used second hand pots from the pot recycling section at our local Mitre 10 (they have these at Bunnings also) and most tubers were planted into individual pots but some were in larger pots in twos or threes or even fours.
When it came time to plant these into my garden beds the tubers in the single pots were much easier to transplant. The other tubers I had to delicately try and separate (by head torch) and I think that this damaged the roots and stunted their growth.
In the scheme of life it was totally fine, but I noticed that the solo tubers did better in those early weeks.
Plant like with like
Because I ended up panic planting (in the dark in the few days before Christmas) there wasn't a lot of planning that went into the positioning of the plants, none were labeled and they were planted too close together.
Sounds like a recipe for a disaster, but it was OK. It just meant that some of the shorter plants that I inadvertently planted between taller plants didn't grow as well.
Support your dahlia plants
Some of the plants stayed short enough and the flowers were small enough that staking wasn't essential, but the dinner plate varieties of dahlia definitely need additional support.
Because I disobeyed the rules when it comes to dahlia plant spacing the plants did a pretty good of supporting each other (kinda like a hedge) and I didn't lose many plants to wind damage until the very end of the season (April) when we had a lot of wind and rain and that was the end of that.
I used individual bamboo stakes and some pantyhose that I cut up into strips (highly recommend you stash the stockings you ladder over the coming cooler months) to try and support my dinner plate dahlia, but this season I will use the netting (this stuff).
Stay ahead of the pests
I think I thwarted slugs and snails and earwigs by using wool around my plants. It doesn't mean that the season was pest free though. I had a section of plants that I'm pretty sure had thrips.
I also ended up with an Army Worm infestation. Not many things give me the ick but Army Worms are officially on the list.
When I had the thrip issue I used Native Neem (you can get it from Mitre 10) and it seemed to fix the issue, because after a ruthless trim the plants came back and flowered by the end of the season.
This dahlia growing season I will be more diligent with the Neem application and will get a proper spray unit (rather than the hand held spray bottle).
