Late Summer Dahlia Care-- Keep Going!!
It’s August— So it’s hot and it’s either wet or dry depending on where you live. Most likely it’s not an ideal climate for your dahlias right now.
It’s been a mostly wet summer here. We had a hot dry patch in early July (complete opposite of last year’s cool wet beginning to July). It’s easy to want to give up right now. I’ve heard multiple times recently— I’m going to quit growing dahlias if they don’t start looking better soon!
Well I’ve got news for you— how they look and perform— that’s up to you (to a degree). Yes, the weather plays a substantial part. But as a dahlia grower, you have to observe and adapt to whatever the weather is throwing at you!
KA’s Mocha Katie (a new personal favorite)
For example, we’ve had thunderstorms that dump loads of water at least 3 times a week recently- sometimes we’ve even gone a stretch of several days in a row of afternoon rain storms. As I walked my field the other day, I began noticing lighter green leaves on the newer growth. This is a sure sign that the dahlias need feeding. Lots of rain means that nutrients are leaching out. One benefit to clay soil even in rain, it does hold more nutrients than a sandy soil. I spent a lot of time earlier this week feeding my dahlias. And with as much rain as we’ve already had this week, I’ll probably feed again before the week is out. I feel like they are behind nutrient wise and a double feed won’t hurt them this time. I wouldn’t normally feed 2x a week but I think they are really low in nutrients right now.
I’m feeding with Alaska Morbloom which is a 0-10-10. I also added some fish emulsion since we’ve had so much rain. I usually stay away from nitrogen this time of year but I could tell the plants needed it. Just keep the phosophorus and potassium numbers (the last 2 in the 3 number chain) higher than your nitrogren when your dahlias are beginning to produce buds and blooms.
I also applied a fungicide. Thankfully I haven’t seen any powdery mildew yet- although with the current weather conditions, that’s not surprising. Powdery mildew can come on fast as it gets later in the season; it’s definitely time to begin frequent scouting for it. With as much rain as we’ve had, I do know we are likely to get other fungal related diseases so a fungicide regimen this time of year is crucial. I sprayed Cease the other day. But I also alternate with Copper and Milstop too. I’ll move more towards the Copper and Milstop rotation as we get later into the season. Those actively kill fungal spores. The Cease is more of a preventative measure and it’s quickly getting past the prevention stage in the field.
Linda’s Baby Dahlia from the side
I’ve also seen some plants just melt down and rot. But with the amount of rain we’ve had, I’m not surprised. Disappointed yes, but not surprised. It’s only a few plants here and there and with heavy rain and heavy clay soil, it’s to be expected. The loss rate is still nothing like the loss rate of last year during the dry heat wave of a summer we had.
BJ”s Dusty Rose
Dahlias in a hot humid climate definitely aren’t for the faint of heart. They aren’t a plant it and forget it plant. But the good news is— there are lots of ways to adapt and I find I really enjoy a crop like dahlias because after 10+ years of growing them, I still learn tons of new tricks every year!
If you are a new grower, hang in there. The pay off is coming. The weather will begin to cool in a few weeks and the dahlias will begin their big show!