Amy:I told you about this on the phone the other day. Something is attacking my lupine.
Some of the leaves furl and curl. I noticed that they all furl towards the left. Weird.
Other leaves turn brown. On the brown ones, it seems as though something is eating the chlorophyll, because the leaves become transparent and brittle.
Most unfortunately, the pest also feasted on the lupine's huge flower bud before it had a chance to burst into the gorgeous, showy pink bloom. :(
None of the other plants around the lupine are affected.
What is it?
Rachel:
Very interesting. First thing, let's figure out what the pest is, then we can address how to fix it.
I see some possible damage by leaf miners, but they may only be a minor problem (Get it? I'm such a dork). I'd like you to check for aphids first, as they seem to love your garden. Now I know you already looked underneath the leaves for aphids, cause I've taught you right. But some aphids cause the leaf to curl over the colony, so they can hide from the sun. Some caterpillar leaf miners and fly miners do this during metamorphosis. So, look inside the folds on the leaves.
See what's in there. If you don't find aphids, then try to take a picture. A little caterpillar would be good, because I sent you some Bacillus thuringiensis. So you already have an organic remedy. If you find aphids, then wipe them off with a damp cloth. When your lacewings get there, you can apply some of them if there are a lot of aphids. Otherwise monitor the plants to make sure the aphids don't take over again. If you find something that looks like a maggot, then we'll need to do some more investigating. If you don't find anything at all, then we need to start considering some other culprits, including diseases.
I see other types of damage. Some bugger has been chomping holes in the leaves. The chlorophyll scraping could be caused by leaf miners, but it could also come from mites or thrips. Both of these are microscopic, so you might want a magnifying glass or loop.
Thrips: Some thrips are big enough to see, others not so much. They leave distinctive damage. With a magnifying glass, you can usually see their poops. (Fun fact, thrips is singular and plural. So you can have a single, lonely little thrips.) Anyway. Look closely at the damaged leaves. Does it look like this? Or does it look like there was something between the layers of the leaf? If you have thrips, then there are some things you should do with the bulbs at the end of the season.
If something was inside, you should be able to find an exit hole through the brown/clear part. That would indicate that you have leaf miners.
Mites: I don't see any webbing, but that doesn't mean anything. Mites are really small and hard to see. If you don't have a magnifying glass, try shaking the leaf over a piece of paper. Look closely for a bunch of tiny dots running in circles. (Fun fact about mites: they have sexual reproduction without intercourse, just like fish. The male fashions his sperm into a little work of art - called a spermatophore - and lays these randomly about. Like leaving out chocolates. The female comes along and decides whether or not to insert it.) Mites are hard to treat, but not impossible. You can even order predator mites, which are like mite assassins! They're kinda fun to watch, if you're into watching dots. It requires a little imagination. But I'm getting ahead of myself.
Some things you can do right away:
1. Examine the plant closely, and make note/take pictures of any bugs you find. Afterward, take a damp cloth and wipe down the leaves. Examine the cloth to see if you got anything you didn't see before.
2. Put some mulch down around the plant. This will discourage thrips, some caterpillars, and maybe whatever is taking big bites.
3. If you find caterpillars, use some of the Bt I sent you.
4. If you find aphids, keep wiping them off every day. Apply some of the lacewings when you get them.
5. If you find mites, then keep wiping it down every day. You might want to wear long sleeves and gloves when you do this, or take a shower afterwards. They won't bite you, but it's gross to have them crawling on you when you can't even see them. Feels kind of "itchy and picky".
I really think you'll find either aphids or caterpillars. At least I hope so. If you don't find anything creating the leaf curls, then we'll have to consider some diseases. That's never fun.