Blotches on sunflower leaves
 

My sunflower has developed brown blotches surrounded by black borders. What
is this? Is it detrimental to the health of my sunflower? How do I treat
it?

Thanks,
Adam

Blotches on sunflower leaves
 

Actually, that's brown blotches with bright yellow borders. I don't know
why I said black...
"Adam Schwartz" wrote in message
news:04IOa.11456$N7.1689@sccrnsc03...
My sunflower has developed brown blotches surrounded by black borders.
What
is this? Is it detrimental to the health of my sunflower? How do I treat
it?

Thanks,
Adam

Blotches on sunflower leaves
 

"Adam Schwartz" wrote in message news:04IOa.11456$N7.1689@sccrnsc03...
My sunflower has developed brown blotches surrounded by black borders. What
is this? Is it detrimental to the health of my sunflower? How do I treat
it?

Thanks,
Adam

What shape are the blotches
What has the weather been
What fertilizers have been applied
What is your watering practice
Do the blotches cross leaf veins

Treatment is unlikely, prevention might be possible.

Blotches on sunflower leaves
 

"Beecrofter" wrote in message
m...
"Adam Schwartz" wrote in message
news:04IOa.11456$N7.1689@sccrnsc03...
My sunflower has developed brown blotches surrounded by black borders.
What
is this? Is it detrimental to the health of my sunflower? How do I
treat
it?

Thanks,
Adam

What shape are the blotches
What has the weather been
What fertilizers have been applied
What is your watering practice
Do the blotches cross leaf veins

Treatment is unlikely, prevention might be possible.

The blotches are of irregular shape. They cross leaf veins. The weather
has been somewhat stormy, but the blotches appeared before the storms. I
water the sunflower thoroughly once a day (it's in a pot). I have not
applied fertilizer but there is a slow release fertilizer in the potting
mix.

Blotches on sunflower leaves
 

The blotches are of irregular shape. They cross leaf veins. The weather
has been somewhat stormy, but the blotches appeared before the storms. I
water the sunflower thoroughly once a day (it's in a pot). I have not
applied fertilizer but there is a slow release fertilizer in the potting
mix.

To be more specific, the blotches seem to stay between the veins for a
while, but eventually they overtake most of each leaf.

Blotches on sunflower leaves
 

"Adam Schwartz" wrote in message news:s%WOa.18897$H17.6046@sccrnsc02...
The blotches are of irregular shape. They cross leaf veins. The weather
has been somewhat stormy, but the blotches appeared before the storms. I
water the sunflower thoroughly once a day (it's in a pot). I have not
applied fertilizer but there is a slow release fertilizer in the potting
mix.

To be more specific, the blotches seem to stay between the veins for a
while, but eventually they overtake most of each leaf.

There are seven kinds of fungal leaf spot disease common to sunflower
and one bacterial and little treatment. Generally bacterial diseases
stay between the veins and fungal ones cross them but once it gets out
of hand even the bacterial ones cross leaf veins.
You can clip off affected leaves if you see any spread.