This is the first year I've tried growing hardy hibiscus from seed. I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants with
their leaves "skeletonized." I'm not sure exactly what kind of caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't seen
any really large ones to know for sure. (The largest I've seen on plants is
about .75" long and about 1mm in diameter.

In the past when I've had problems with these kinds of bugs, I've sprayed
BT. I started doing that this season. Unfortunately, we've had almost
daily hard rains that I'm guessing makes it hard for the treatment to stay
on the plant. I've sprayed repeatedly with BT and the plants keep getting
eaten and live worms are still on the plants. At one point I thought my BT
had gone bad since it was from last season. I bought now BT and still the
problem persists.

Can anyone offer any recommendations? So far the bugs only seem to be going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May. I
think I need to move on to something else.

Tony

Tony said:

This is the first year I've tried growing hardy hibiscus from seed. I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants with
their leaves "skeletonized." I'm not sure exactly what kind of caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't seen
any really large ones to know for sure. (The largest I've seen on plants is
about .75" long and about 1mm in diameter.
snip
Can anyone offer any recommendations? So far the bugs only seem to be going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May. I
think I need to move on to something else.

Sawflies. Unlike lepidoptera caterpillars, Bt won't do them in. If the situation
is beyond hand-picking, try an ultra-refined horticultural oil (safe for use in
summer) or a pyrethrum-based insecticide.

Has links to pictures:

http://www.hgic.umd.edu/diagn/flow/sawflies.html

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)

Lucky I saw this post. I got them too! I just hope they have not killed my
hibiscus. I tried BT first, and thought mine was too old, because it didn't
work. I found some 5% Malathion and doused them with it yesterday, and it
seemed to be working. I will know more in a little bit. They are a tough
little worm!
Bill in TN

"Pat Kiewicz" wrote in message
...
Tony said:

This is the first year I've tried growing hardy hibiscus from seed. I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants
with
their leaves "skeletonized." I'm not sure exactly what kind of
caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't
seen
any really large ones to know for sure. (The largest I've seen on plants
is
about .75" long and about 1mm in diameter.
snip
Can anyone offer any recommendations? So far the bugs only seem to be
going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm
not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May.
I
think I need to move on to something else.

Sawflies. Unlike lepidoptera caterpillars, Bt won't do them in. If the
situation
is beyond hand-picking, try an ultra-refined horticultural oil (safe for
use in
summer) or a pyrethrum-based insecticide.

Has links to pictures:

http://www.hgic.umd.edu/diagn/flow/sawflies.html

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)

Thank you! That's them! I've even seen the adult and didn't recognize it.

Thanks for the help I'll try horticultural oil.

Tony

Shortly after
"Pat Kiewicz" wrote in message
...
Tony said:

This is the first year I've tried growing hardy hibiscus from seed. I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants
with
their leaves "skeletonized." I'm not sure exactly what kind of
caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't
seen
any really large ones to know for sure. (The largest I've seen on plants
is
about .75" long and about 1mm in diameter.
snip
Can anyone offer any recommendations? So far the bugs only seem to be
going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm
not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May.
I
think I need to move on to something else.

Sawflies. Unlike lepidoptera caterpillars, Bt won't do them in. If the
situation
is beyond hand-picking, try an ultra-refined horticultural oil (safe for
use in
summer) or a pyrethrum-based insecticide.

Has links to pictures:

http://www.hgic.umd.edu/diagn/flow/sawflies.html

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)

Be sure and don't use Malathion as I did above. I may have overdosed them,
but it looks like I not only killed the worms, but the Hibiscus too! Rats!

I wonder if soap would have worked?
Bill

"Tony" wrote in message
...
Thank you! That's them! I've even seen the adult and didn't recognize
it.

Thanks for the help I'll try horticultural oil.

Tony

Shortly after
"Pat Kiewicz" wrote in message
...
Tony said:

This is the first year I've tried growing hardy hibiscus from seed.
I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants
with
their leaves "skeletonized." I'm not sure exactly what kind of
caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't
seen
any really large ones to know for sure. (The largest I've seen on
plants
is
about .75" long and about 1mm in diameter.
snip
Can anyone offer any recommendations? So far the bugs only seem to be
going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm
not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May.
I
think I need to move on to something else.

Sawflies. Unlike lepidoptera caterpillars, Bt won't do them in. If the
situation
is beyond hand-picking, try an ultra-refined horticultural oil (safe for
use in
summer) or a pyrethrum-based insecticide.

Has links to pictures:

http://www.hgic.umd.edu/diagn/flow/sawflies.html

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)

We've grown the hardy hibiscus for years and had to deal with this pest. We
noticed that if you spray with Orthene at the first sign of damage (usually
in the lower leaves), there's no problem for the rest of the year. We've had
some years where they were practically defoliated. Orthene has been our best
bet.

"Pat Kiewicz" wrote in message
...
Tony said:

This is the first year I've tried growing hardy hibiscus from seed. I've
got some plants in the ground and some in pots. Unfortunately the
caterpillars are devastating them. I'll go out and find entire plants
with
their leaves "skeletonized." I'm not sure exactly what kind of
caterpillar
is doing this. It resembles a hornworm in color/shape, but I haven't
seen
any really large ones to know for sure. (The largest I've seen on plants
is
about .75" long and about 1mm in diameter.
snip
Can anyone offer any recommendations? So far the bugs only seem to be
going
for the hardy hibiscus (and possibly a nearby mexican petunia, but I'm
not
for sure on it).

These plants have been sprayed at least 6 times with BT since late May.
I
think I need to move on to something else.

Sawflies. Unlike lepidoptera caterpillars, Bt won't do them in. If the
situation
is beyond hand-picking, try an ultra-refined horticultural oil (safe for
use in
summer) or a pyrethrum-based insecticide.

Has links to pictures:

http://www.hgic.umd.edu/diagn/flow/sawflies.html

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)