The Importance of the Right Name
When learning about a pest, begin your journey by finding out it’s scientific name. The bug I’m ruminating on today is the Green Vegetable Bug Nezara Viridula, also called green vegetable beetle, stink bug or shield bug. These other names bring you to an array of bugs, not necessarily Nezara V. With the proper name you can’t go wrong. Searching with the scientific name brings you to the best information.
Beware Their Many Disguises
Green Vegetable Bugs go through many phases, each one quite different from the last. The girls were picking beans for tea and came rushing in to get the camera to photograph the cute bugs they’d found. Newly hatched Nezara they were (and they are cute.) Here’s some excellent photos to acquaint yourself with all the phases (instars).
There is a native green vegetable bug which looks similar, but doesn’t have the three light spots along it’s ‘shoulders’. Don’t worry about him, he wont damage your crops.
Natural Predators
Being stinky and big they wont be ambushed by an Assassin bug or eaten by a bird. Predators and parasitic wasps get a look in at the egg stage (black eggs indicate a parasitic wasp has been at work), but maybe not as often as we’d like, Mrs Stink can be quite the egg protector.
Digital Control
I love this term, as if you can press a button and the problem is solved! Pre-infestation (because getting pests at the first sign is the way forward), GVB’s are easily managed by picking them off – especially in the morning (am sure you can relate to getting going slowly), or on a cold day. While you’re at it check under the leaves for tidy clusters of pale, barrel-shaped eggs and rub them off.
Squash one bug and the smell will alert all, sending them plummeting to the ground en masse. In my heavily mulched and over planted wilderness this guarantees their escape. Should your garden be more manicured, you could use this to your advantage. I’ve heard tell of sheets laid down to catch them when they fall. Or rather than squashing them, toss them into a bucket of soapy water as you go.
Success with Neem
If the population is left to grow (about 100 eggs per season per Mrs), then the damage is big – plant malnutrition, undeveloped fruits and ruined fruits (leaving dry, corky bits – see my poor raspberry!). They pierce then suck – especially loving the fruits.
Anything eating your plants is theoretically impacted by Neem, so I asked Bonny from Naturally Neem, if Neem would work on Green Vegetable Bugs. Yes, she said, but the trick is to spray intensively – 3 times a week. It does work.
Neem is not a contact killer, it only damages the insect after it’s been ingested, which is why it doesn’t impact the beneficial insect population. Though Neem is low level toxic to bees, I always spray early morning or late evening once the bees have toddled off to bed.
Everything does of course impact, even ‘friendly’ things. Our human joy is that we have no idea of the impact of our interventions. Use these tools as you must, but know that less is more and we are stronger by far when we intervene as little as possible.