Three Different Dahlia Issues
I'm having issues in my dahlia bed. As an example, I've got three dahlias being grown in grow bags that are a foot apart from each other, yet each one has what appears to be a different issue. One has mottled, yellowing leaves with traces of grainy white flecks.
The next has leaves with light spots affecting the top of the leaves.
The third has some sort of damage on the stems and underside of the leaves -- brown blotches that almost look like aphids at first glance but are not.
My entire dahlia garden has been affected by leaf miners, and over the past several weeks I've sprayed an insecticide containing Spinosad on them, as well as Safer's EndAll spray, which contains Neem Oil, Pyrethrin, and fatty salts. I'm surprised I'm still having so many issues after applying these sprays as directed. :/
Any ideas of what could be affecting my cherished dahlias?
Comments (9)
ken_adrian Adrian MI cold Z5
3 years agoraymondo17
3 years agoThanks for the reply.
>what did you fill the grow bags with ...<
Kellogg Garden Organics' Raised Bed & Potting Mix.
>loction.. big city name... weather since planting ... watering schedule ... what if any fert etc ...<
Zone 9, Northern California, Sacramento region. Typical Sacramento summer with highs in the upper 90s, occasionally tipping into the lower 100s.
I've been experimenting with the watering. They're on a drip line with 1-gallon-per-hour emitters. I have two emitters positioned above each bag. I started out the summer by giving them 3 hours of watering time every other day. I then went to 1 hour of watering time every day. I'm currently dividing that 1 hour into two sessions, one early morning, one mid-day.
As for fertilizer, every other week or so I've been giving a combination of fish emulsion and molasses. I recently tried Tomato-Tone fertilizer (NPK 3-4-6), first as a tea, then this past weekend digging it into the top layer of soil.
>why are they cherished<
They are cherished because my dahlias are just about the only thing in my garden this year doing even half-way decently. I used to have very good success in the garden, but for several years now I've been having terrible results. My tomatoes (which are in the next raised bed and on the same watering line) used to tower over me at 11' tall, and now they barely come up to my waist. I attribute this to the fact that we have a huge tree (that keeps getting bigger) which shadows the garden. I'd estimate the garden gets about 5 hours of direct sun a day. Perhaps that's the underlying issue?
The huge tree also sends up feeder roots into the raised beds, which is why I tried growing in grow bags this season, so the feeder roots wouldn't suck all the moisture from the plants.
So light? Watering? Fertilization? I hope my novel here provides some insight on why my garden has been doing so poorly the past couple of years.Related Discussions
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3 years agolast modified: 3 years agoHU-461092274
3 years agoraymondo17
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HU-461092274