Each season brings a new set of insects to the garden. These are some of the insects we found and the pest management we tried in the 2020 season.
|May/ June||Aphids (black)||Artichokes and fava||Insecticidal soap|
|July/ August||Beetles (Japanese and Asiatic)||Basil, sunflowers, rhubarb, peppers, marigolds||Neem oil (peppers)|
|July||Striped cucumber beetle||Cucumbers||None|
|July-Aug||Squash vine borer (SVB)||Winter and summer squash||Sticky traps with SVB lures|
|July||Horn worm||Tomatoes||Hand removal|
|July||Flea beetles?||Tomatoes, eggplants||None|
|July||Flying aphids?||Jerusalem artichokes||None|
|July-Sep||Cabbage worms (green and striped)||Cabbage, kale||Hand removal|
|Oct||Aphids (grey)||Rutabaga, kale, brussels sprouts, cabbage||Insecticidal soap weekly|
[May/June] Spring aphids on the artichokes
The artichoke seedlings were beautiful when they were transplanted, but within a few weeks, the undersides of the leaves were covered with black aphids.
We sprayed the artichoke leaves with insecticidal soap to reduce the aphids, but the leaves were seriously damaged after spraying (leaf burn?) and the aphids continued to be a problem through the summer.
Lisa grew one of the extra artichoke seedlings in a similar-sized pot at her home and did not have any aphids on the plant. We aren’t sure what caused the aphid infestation on the garden artichokes or how to manage it.
[July] Beetle damage on the basil, peppers, rhubarb and sun flowers
The basil and rhubarb leaves were decimated quickly. We never found any insects on the plants, but the skeletonized leaves were consistent with beetle damage. In addition to the leaf damage, some peppers also had bug damage in the fruit. We didn’t use any spray or treatment early summer, but later in the summer, around August, the peppers were sprayed with neem oil once a week. Results are inconclusive, but there seemed to be some improvement with the neem spray.
[July] Cucumber wilt from striped cucumber beetle
In late July, the cucumber plants began to wilt and Lisa noticed these yellow and black striped beetles on the cucumber vines and took the photo below. The beetle has a black head as opposed to the similarly striped potato beetle which has a yellow head. Adult cucumber beetles can carry and transmit a bacteria to cucumber vines that causes wilt and damages the fruit. The articles below have some information about the beetle and treatment options.
[July] Squash vine borers
Squash vine borers typically attack the summer squash, delicata and pumpkins in the garden. We monitor the vines closely for frass and have to hand remove the larvae from the stems. The butternut squash is usually resistant to the borers.
This summer, 2020, was the first time we tried using traps to catch the squash vine borer moths. We purchased 2-packs of the trap from VivaGrow! and placed two in the garden in late June. We hung them about 2 feet above the ground in a bed a few feet away from the squash plants. Within a week, there were several squash vine borer moths (and other bugs) in the traps.
We added two fresh traps after about 2 weeks and caught a few more moths. The majority of the moths were caught in June, though.
In July or August, we did find some borers in the summer and winter squash, but it seemed like fewer than normal and the plants survived and continued to produce squashed much longer than normal. The traps felt like a successful experiment and we will probably repeat it next year.
[July] Flea beetles?
Several varieties of the tomatoes had small but densely packed holes in the leaves and some small insects were observed on the leaves as well. The leaf damage appeared consistent with flea beetles, but this has not been confirmed. We did not apply any treatment to the tomatoes to try to mitigate the leaf damage, but the productivity of the plants was great and the fruit did not appear damaged with the small holes. Since the impact to productivity and quality was not noticeable, we probably do not need to worry about treatment for flea beetles on the tomatoes.
The eggplants also had small, densely packed holes in the leaves that might be due to flea beetles or something similar. With the eggplants, the holes were not limited to just the leaves — some of the fruit also had small holes and bugs inside. The bugs inside the eggplants appeared to be small larvae a few millimeters long, so this may be an unrelated pest.
[July] Flying aphids?
For a short period (a week or two), the jerusalem artichokes were covered with small insects plus a few larger flying ones. The initial thought was that they might be flying aphids. They did a fair amount of damage to the leafs of the jerusalem artichokes, but we didn’t see them spread anywhere else in the garden so we did not spray or treat them.
[Jun-Aug] Cabbage worms
Green cabbage worms are usually found on the green cabbage starting around June, but the worms are also occasionally found on the collards, kale, cauliflower and broccoli. They are difficult to spot since their color blends in so well with the leaf, but usually the tell-tale sign is the frass near the new growth in the center of the cabbage. When we see fresh frass, we keep searching until we find the worms and hand remove them to stop the damage. Sometimes, large amounts of frass are from one large worm like the one in the picture, but it can also be from multiple worms in the same plant.
[Late Oct] Fall aphids on… well, just about everything!
The second round of aphids in the garden hit around October and they are light gray rather than the black aphids found in the spring and summer. These gray aphids appear quickly and cover the plants. We spray with insecticidal soap regularly, but it seems like once the gray aphids infest a plant, it is next to impossible to get rid of them.
All four pole bean varieties were harvested this week (Sep 19).
Trionfo Violetto was the earliest to mature and is very prolific. The other three varieties took 2-3 weeks longer to mature, but were all harvestable around the same time. We noticed some thin rusty blemishes on some of the surface of the Blue Lake beans (seen in the close-up picture), but it’s not clear whether the blemishes are a concern.