Last year squash bugs, this year it's beetles.
We're beginning to think we're not meant to grow our own
cucumbers and squash. Any advice for keeping little striped and
spotted beetles from devouring all the leaves, and squash bugs from
sucking them dry? We're growing organic, so tell us what we can do
without standard pesticides. - C.C. -
In organic gardening, being there is not half the battle, it's
the whole thing. Check the plants often and you can probably stay
ahead of this game with manual
We think our approach is in line with most others who grow
organically and done time in beetle battle or on a squash squad. To
garner any new tactics out there, we've also created a place for
others to add those suggestions, too. Keep an eye on that spot in the Forum.
First, the squash bugs, now...
Right now, inspect the leaves, especially the undersides.
Scrunch the bugs -- wear gloves to avoid acquiring their
stink -- and smash their eggs. Alternatively, collect the eggs you
find and put them on a dish at your bird feeder. It's very
satisfying to watch goldfinches and chickadees scarf bug eggs.
Squash bug eggs are in groups up to 20, tan to yellow,
darkening as they age. They hatch in about a week, so patrol
thoroughly at least once a week to undo the efforts of the first
group of squash bugs. Cut that batch short and you avoid the hordes
that can come from Generation Two a month later.
Alternatively, or in addition, clear the mulch away from the
bases of the vines so there are less hiding spaces, and apply
pyrethrum or diatomaceous earth -- powder from shells of very tiny
marine crustaceans, a dust that kills soft bodied insects via
desiccation. (The insecticide pyrethrin is allowed in most organic
programs. It is derived from Pyrethrum/painted daisy flowers.)
...and in fall
Then as harvest ends, clean up very well around the garden to
reduce hiding places for overwintering bugs. Burn or hot compost
all plant debris. Scrape and store wooden accessories dry and well
above ground. Hoe or till at least once in late fall to expose any
adults that burrowed in.
Next year, grow bug-resistant squash and cukes, if these choices
suit your use: Blue Hubbard squash, Ashley or Gemini cucumbers,
There is plenty of great advice available in Extension
bulletins, especially if you use
technical terms as you search and apply an "Images" filter. For
instance, here is this very practical, well illustrated publication
from Colorado State University Extension.
Leaves with pale or wilted spots, and sunken holes?
Squash bugs have been at work. Ragged holes chewed in the leaves?
Stem bases scraped? Cucumber beetles. Both pests have been at work
Now, about cucumber beetles, spotted and striped
These are tougher to control because they lay their eggs in
crevices in the soil around the base of the plant. While the
scraping, chewing damage the adults do is infuriating, it may be
the gnawing on roots and stem base that the grubs do, that does
Note: Information about cucumber beetle eggs and squash bug eggs
has become tangled, in books, on the Internet, even in Extension
publications. Ignore references to beetle eggs laid on leaves. Once
in a while you might find striped cucumber beetle eggs in groups of
20+ on ground level leaves but most of the time they deposit those
eggs in the ground. Spotted cucumber beetles lay eggs around the
base of other plants, not the cucurbits. Their alternate hosts
include corn, peas, potatoes, grass and quite a few others.
Track and squish the beetles every time you're in your garden.
Make those visits frequent during June. Be glad if you're in the
northern U.S., as we are, because we have just one egg-laying
generation per year to hunt down.
It was probably cucumber beetles that scarred this stem
base. Look where the arrow points and you can probably see two eggs
Keep your guard up
Having had cucumber beetles once, expect them the next year, as
early as the soil is warm enough to set out cucumber plants. The
overwintered adults will come to those new plants to lay eggs, so
cover your transplants or seeded rows with floating row cover and
leave them covered until flowering time when you will have to open
them to pollinators for at least a few hours a day. Fortunately by
then most of the cucumber beetles will have done their egg laying
and your plants won't suffer grub chewed roots and stem bases.
Below, left: Striped cucumber beetles. We just love to
interrupt pest bugs' mating dances. In our personal kill count, we
award ourselves bonus points for two at once.
Below, right: Spotted cucumber beetle is also called corn
root worm, for its attraction to corn plants at egg laying
We jest in all
In case it irks you to hear this called a "game:" We're not
being flippant, only practical. It's a grim humor with which we
entertain ourselves, in bug crunching much as we do in weeding. We
joke as we hunt, and compete with ourselves and each other for
total killed. "Take that you devil!" "Ah ha, two at once!" Etc.
If there are children about, we're not above hiring them as
accomplices if they're old enough to hunt without crashing about in
the plants. We pay per bug! Like you, we spend a lot of time and
not a little money on seed, plants, plant protection and
accessories, so we aim to harvest.
powerful to curse it by name, our
Also, we hunt information as well as pests. In that we've
learned to look for a pest's scientific name (whether fungus or
beetle, it has an official name). Once we have it, we use that in
Internet- and reference book searches. Wit that key, we can often
cut straight to information from the most qualified sources.
Squash bug: Anasa tristis
Striped cucumber beetle: Acalymma vittata
Spotted cucumber beetle: Diabrotica undecimpunctata