Robbins Farm Garden is a cooperative community garden project at Robbins Farm Park in Arlington, MA. Since 2010, we’ve grown vegetables organically as a group, created an educational resource in the community and continued the agricultural tradition of the farm at the park. We garden Saturday mornings April – November and Tuesday evenings June – September. The project is run through Arlington’s Recreation Department.
2020 Garden Pests
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.
| Month | Insect | Plant | Treatment used |
|---|---|---|---|
| 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.
Aphids on artichokes: 6/16 
Leaf burn on 6/27
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
July 25 peppers 
July 18 rhubarb 
July 20 Skeletonized basil plants
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.
- http://growingideas.johnnyseeds.com/2010/04/pest-of-week-striped-cucumber-beetle.html?m=1
- https://extension.umn.edu/yard-and-garden-insects/cucumber-beetles
[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.
Kale 10/18 
Rutabaga 10/24
Four Pole Bean Varieties
Four pole bean varieties 
Kentucky Wonder 
Trionfo Violetto 
Blue Lake 
Blauhilde
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.
Lima Beans
One of our experimental crops this summer was Henderson’s Bush Lima Beans from Rohrer. They are described as a prolific heirloom variety with smaller 3-4″ pod.
By early August, the plants were loaded with flowers and beans and they can continue to produce for months until the first frost. Since they have a long growing season and pods can be at different stages of maturity, we weren’t sure how to decide on whether a pod was ready to pick or not.
The pods grow to about 3-inches long and seem to go through 3 stages once they reach that size:
1) relatively immature where the pod is full length, but it is still flat-ish and the beans inside are very small and difficult to shell
2) mature where the pod looks about the same size, but the girth fills out as the beans expand inside
3) dried.
The pods dry out on the plant surprisingly quickly, so the transition from mature to dried might happen in week or so. Some of the earliest dried pods we found had very small beans inside. It was discouraging at first because it seemed to suggest that the limas would be small, no matter how long we waited to harvest them. Fortunately, that wasn’t the case though. After a couple weeks of harvesting, the mature limas beans that we picked were larger.
With the first big lima harvest of the season, I decided to try sorting the beans as I shelled them to try to figure out what signs we could look for when deciding which beans are ready to pick. The biggest limas had a pod that felt full to the touch and I think the shell starts to turn a little paler green in color like the unshelled pods in the second column of this photo:
On the left are the dried beans. Those are easy to tell apart. In the middle are the mature beans. Most of the mature pods were plump to the touch. On the right are the less mature beans which were a deeper green on the outside. These took a lot more effort to get out of the shell and the beans inside were smaller and still a little green instead of the bright white color of the mature limas. It was tricky to tell some of these immature pods apart from the mature ones because the immature ones had also filled out, and were plump to the touch. I found the slightly yellow/pale color on the plump pods to be the best clues that the pod was mature and would shell easily.
Both the green and white limas tasted good. The main difference was the size of the bean and the effort to shell them.
Take way: Harvest pods when they are plump to the touch and the color is just starting to pale (lighter green).
In the end, I had a nice pile of shelled limas, some were big, others small; some had turned white, others were different shades of green:
I just boiled the limas and served them with salt and pepper. They all tasted pretty good, even the little green ones!
As for the dried beans, they were extremely easy to shell but there are only a few of them, so not sure how the dried ones taste yet. Interestingly enough, the dried beans seem to be a little smaller than the mature limas. Perhaps they shrink a little as they dry out?
Fence update
Mike, Michael and David planted all five of the new fence posts on the far side of the garden in one day! (Well almost – one still needs some digging). I (Alan) finished the rails on the Eastern Ave side. If the weather is good Tuesday evening, I’ll oil the rails, and should be ready to hang the fence fabric next Saturday. I have no doubt now we can finish this season.
The general fence-building process is:
- Measure and plant the metal post bases, in a reasonably straight line, evenly spaced, right height, and plumb. Every so often we get lucky and just pound one straight down without any digging. Most of the time we need to dig a hole, get the post base in the right position, and pack the hole with rocks and dirt to hold it firm.
- Cut a notch in each 4×4 posts for the irrigation lines and paint them with raw linseed oil.
- Cut and fasten the 1×4 rails, making everything nice and square, and paint them with raw linseed oil.
- Screw and staple the 1×1 hardware cloth to the posts and rails and trim up the edges.
- And when the new fence is finished, we need to disassemble and dispose of the old one.
A couple of challenges left – we’re recycling about five post bases that are currently holding up the old posts, so we need to at least partially disassemble the old fence to finish the new one; what do we do with the Philosopher’s Stone?
Mid-season – a time of transition
Mid-summer is a time of transition in the garden. Today we pulled the spring peas and replanted the area with pole beans. (We use the same tall trellis for both.)
The garlic was also harvested today and replanted with turnip seed. Last week, we harvested the first spring broccoli and cabbage, and the last of the fava beans, which were replanted with fall peas.
Harvesting of our heat-loving nightshades (eggplant, peppers and tomatoes), okra and squashes (cucumbers, crooknecks and zucchini) has begun and the first of our bush beans were ready today.
Our everbearing greens (collards, kale, perpetual spinach and Swiss chard) are in full production and the sequentially-planted greens (arugula, mustard and lettuce) have been providing continuous harvests.
Next week, the first of the potatoes should be ready for harvest. That will herald replanting with fall brassica seedlings (broccoli, cabbage and cauliflower) seeded last month in our nursery bed.
The last of our spring salad turnips and the first of our onions were also harvested today. There is much to look forward to, and it’s feeling like the garden is in full swing!
COVID-19 Garden Guidelines (updated)
A sign has been posted at the garden with guidelines for gardeners to follow in order to grow our food and keep everyone safe during this health crisis. A pdf of the sign is available here. The text appears below.
TO DO OUR PART TO STOP THE SPREAD OF COVID-19
WE ENCOURAGE GARDENERS TO:
• Stay home if you or those you live with are not well or not sure.
• Maintain physical separation of 6 feet or more.
• Avoid clusters (of more than 10), schedule gardening at different times.
• Use your own tools and take them home.
• Don’t leave things outside the fence while you’re working.
• Ask visitors to stay outside the garden fence.
• Use gloves and sanitizer to keep your hands clean.
• Cloth masks are (required).
• Sanitize commonly-touched surfaces: gate, locks, water spigot, hoses, storage bin, seed box, fertilizer bags.
Last harvest of 2019 – parsnips
We left the smaller parsnips in the ground last fall and harvested them today.
The ground was already pretty workable, probably due to lack of rain, but still pretty cold.
First 2020 seedlings are up
The artichoke and allium seeds we planted on February 22 are off to a strong start. The front row has 1 pot of Tavor artichokes & 3 of Walla Walla onions; the middle row has 2 pots of Rossa di Milano red onions & 2 of Conservor shallots; the back row has 2 pots of Megaton leeks & 2 of New York Early storage onions. Next week, we move on to seeding our first brassicas and greens.
Seedling Starting Mix: soil recipe revealed
We’ve been making our own seedling soil for a decade. Yet, this is the first time we’ve attempted to document it as a recipe. For germinating seeds, like the leeks, onions and shallots we started yesterday, we use a light, less nutrient-rich mix.
- Coconut Coir – 1 brick (rehydrates to 0.33 cu ft)
- Compost (sifted & sterilized ) – 12 cups
- Vermiculite – 3 cups
- Sand (rough builder) – 3 cups
- Garden Tone fertilizer – 2 TBS
- Wood Ash – 2 TBS
- Limestone (ground) – 1 TBS
For transplanting the seedlings into 6-packs and small pots, we shift the mix closer to fertile garden soil by increasing the compost and nutrients.
- Coconut Coir – 1 brick (expands to 0.33 cu ft rehydrated)
- Compost (sifted & sterilized ) – 24 cups
- Vermiculite – 3 cups
- Sand (rough builder) – 3 cups
- Garden Tone fertilizer – 4 TBS
- Wood Ash – 4 TBS
- Limestone (ground) – 2 TBS
About the ingredients:
The coir is made from ground coconut shells, and is a pH-neutral, sustainable alternative to peat moss.
The compost is all vegetable-matter based, from a home compost pile and from the ones at the main garden.
The Garden Tone organic fertilizer is rated at 3-4-4. For our eggplant, pepper and tomato seedlings, we often substitute Tomato Tone.
The wood ash is collected from a home fireplace, sifted to remove charcoal chunks.
The limestone buffers the pH of the compost. We use pure ground limestone. (Our garden soil tests high for magnesium, so we’re wary of adding more.)
2020 Seed Selection Meeting – February 1
Save the date – our annual Seed Selection Meeting will be on Saturday, February 1st in Community Room of the Arlington Police Headquarters from 10 am to 1 pm.
Everyone interested in the crops & varieties we will grow at Robbins Farm Garden this season is welcome. Prospective new members of the garden group are especially encouraged to attend and join in the discussion. Bring your seed catalogs and great expectations for the season to come!
The Arlington Police Headquarters is at 112 Mystic Street. When you enter the building, go directly up the stairs; the community room door will be on your left.
2019 Notes to the Future (end of season notes)
General Comments:
- Many of the seedlings were affected by putting too much Coast of Main fertilizer in the potting soil – some peppers and lettuce died, some eggplant and onions were stunted, tomatoes were okay.
- Several crops were affected by rodent predation: corn, eggplant, tomatoes, watermelons and, to a lesser extent, both winter squashes.
2019 Alliums (end of season notes)
Garlic: very good, do again
Leeks: be more careful in planning for raised bed later in season, otherwise very good, do again
Onions: Sets did well. Seedlings suffered from over-fertilization of potting soil, most did well
Scallions: did fantastic in crappy soil, try rows @ 2” apart next year
Shallots: did well, but didn’t have two full rows of seedlings due to over-fertilizing potting soil
Walking Onions: did well, provided beautiful scallions in spring, transplanted bulblets over several weeks
2019 Brassicas (end of season notes)
Broccoli: early crop very good – fertilized when heads begin to form. Late crop did well too, good number of side shoots after main heads
Brussels sprouts: no aphids this year, some sprouts stayed small, but overall good. Plant on north side of bed next year to keep from shading bed
Cabbages: early crop did well, except some had rot at the base (disease?). late crop didn’t mature well, lots of cabbage worms – two types and late into season, also shaded by Brussels sprouts
Cauliflower: early crop was very good, do again. Late crop was the best yet, but plants had signs of Black Rot on the leaves (look into seed supplier and succession planting in beds)
Kohlrabi: fantastic, do again
2019 Carrot Family (end of season notes)
Carrots: single crop of different varieties worked, most did well (Mokum not as good) a fair number of split roots this year
Celery: late (seedlings had to be replanted), but all were stocky and healthy, didn’t lose any to disease
Parsnips: good germination & thinning, but not as perfect – some stubby and with nodules – research
2019 Flowers, Grains, Herbs, etc. (end of season notes)
Basil: lost some seedlings to over-fertilized soil, plants that survived were okay, some dark spots (disease?)
Cilantro: both plantings were excellent, even though second planting began while shaded by squash leaves
Herbs: Chives all did well, divide in spring; Lavender old growth died over the winter but sprouted tons of new growth in spring; Lemon Balm did great, divide in spring; Rosemary that Steven wintered over was awesome; Savory did great, divide or root prune in spring; Tarragon was sad as usual (research), Thyme doing great (replaced English thyme plant in spring)
Nasturtiums: best ever, dense & productive without the mid-season die off, caught spring aphids early; no fall aphids
Okra: new variety a winner: didn’t lose any seedlings, pretty, uniform, vigorous, productive & tender when oversize. Try pruning early in season to make plants bushier
Popcorn: great germination on new variety, very pretty but tops of ears munched by caterpillars and entire patch was attached by some critter (rats or raccoons?) before all could be picked, thin to 1 plant per space if we grow again
Rhubarb: did okay, some leaf damage – beetles?
Sunflowers: 3-4 germinated and produced well, lower leaves eaten by Asiatic and Japanese beetles
2019 Greens (end of season notes)
Arugula: very good, do again
Bok Choi: early crop bolted, late crop didn’t germinate well, transplants did better than those left in place
Collards: not as robust but did okay, some leaf damage, check variety and seed source
Kales: did fine (dinosaur did better than usual), some leaf damage, try Redbor next year?
Lettuce: first several crops did great (except for over-fertilized 2nd indoor planting), some rot on denser plantings, thin better, try some disease-resistant varieties next year
Malabar Spinach: not stellar, can’t compete with nasturtiums
Mesclun: did okay in poor real estate, wasn’t reseeded, so became Red Russian kale bed later in season
Mustard: did well, reseeding well scheduled, green lasted longer than red
Perpetual Spinach: germination not great, but did okay in poor real estate
Swiss Chard: did okay, well thinned, research if more fertilizing and/or changing soil pH would help
2019 Legumes (end of season notes)
Beans (bush): Dragon’s Tongue did great, Maxibel were very productive and attractive, Antigua not nearly as good, chicken wire protected bed from bunnies
Beans (dried): weren’t productive (maybe shaded by dense corn plants) bunnies kept away with chicken wire fencing when seedlings were young
Beans (pole): purple did great, try to find Garden of Eden seed again, Kentucky Wonder & Blue Lake did better than Kentucky Blue (beside Philosopher’s Stone)
Fava Beans: did great – productive, no aphids or wooly bear caterpillars
Peas: spring crop productive, Tall Telephone germinated poorly (next to Philosopher’s Stone), Sugar Snaps didn’t seem right – check seed source. Fall crop was highly productive, planted at the right time and covered with shade cloth to keep soil cool
Soybeans: did very well, but needed to infill plant twice, some Japanese beetle damage to leaves
2019 Nightshades (end of season notes)
Eggplants: failed to thrive – Orient Express & Japanese White Egg produced better, Black Beauty way too slow (try different variety next year), JWE & BB fruits had lots of small holes – insects (research)
Peppers: not a good year – disease? nutritional problem? over-watering? Potted plant experiment was inconclusive – pots were shaded and plants were from nursery. Lunch Box did better. Corno di Toro and Cheyenne did less well.
Potatoes: very good, do again
Tomatillos: always take too long to produce fruit, fertilize more?, mysterious picking happened mid-season, topped plants when Brussels sprouts were topped to reduce # of smaller fruits
Tomatoes: beautiful plants, excellent productivity, good fertilizing & pruning, Actinovate used in soil before planting and every few weeks for most of summer, lots of hornworms! Also serious rat predation – inflatable snakes helped late in season, maybe try chicken wire? Topped plants near end of season to put energy into ripening fruit. Place taller cherry tomato bed on north side of other bed. Consider non-wood stakes to limit soil-borne disease. Ramapo plants were strange – check seed supplier. Randy Boys not as vigorous or productive as others.
2019 Root Crops (end of season notes)
Beets: excellent crop, resilient and productive
Jerusalem Artichokes: flourished in same space as previous 3 years
Radishes: early crop did fine. Late crop okay too
Rutabagas: excellent – good germination and thinning – one was the size of a softball, a few were tiny
Sweet Potatoes: did great, good yield, had more Murasaki than expected
Turnips (cooking): very good, do again
Turnips (salad): early crop was incredible – best ever. late crop never fully matured – not good real estate
2019 Squash Family (end of season notes)
Butternuts: high yield, biggest came from 3 sisters plot. Try fertilizing more, maybe grow new super-tasty variety next year?
Cucumbers: good yield, the right ratio of slicing/pickling (4/2), slicing type did better than pickling, mildew not as bad, one plant ended up in 3 sisters plot
Delicata: produced well, planted more this year (fewer pumpkins), vine borers were a problem & were in actual squashes this year
Pumpkins: did well, produced 1-2 per plant (better than previous years)
Watermelon: much better this year, yummy and big, soil-borne disease took half the seedlings after planting, plant twice as many seedlings again next year, rat predation on later fruit
Zucchini: green did better than yellow, fewer borers, second crop didn’t reach full potential again
Field Day at Robbins Farm Park
How much water?
While I was watering the other day, I was wondering how long to keep the hose on each bed. Of course that depends on many factors, but I’m looking for a rule of thumb.
First I need to know how much water comes out of the hose:
With the water on full and the nozzle on “shower”, it took almost exactly 1 1/2 minutes to fill a 5-gallon bucket. So that’s 3 1/3 gallons per minute.
Our garden beds are about 6×9 feet, or 54 sf = 7,776 sq in. So 1 inch of water on the whole bed is 7,776 cubic inches. There are 231 cubic inches in one gallon of water. So it takes 33.6 gallons (evenly spread) to get one inch of water onto the bed. At 3.33 gallons/minute, that’s about 10 minutes.
How much “rain” does a vegetable garden need? According to numerous sources (like this one), about one inch per week, total. That’s convenient – 10 minutes of hose time per bed per week, evenly spread, if it never rains.
Of course, that’s a very broad guideline. Mature plants with deep roots could probably be watered with the whole inch once or twice per week. Newly planted seeds, seedlings, and transplants need to get water probably every day, because the roots are so shallow and the little plants have no capacity to store moisture.
Too much watering can be almost as bad as not enough. Soil around mature plant roots needs to dry out so the roots can get oxygen. Sometimes yellow leaves indicate too much water. A number of sources say that watering tomatoes too much compromises the flavor (like the discussion in this article about “dry farming”, which claims that stressed tomatoes taste better).
Wilting in the hot sun is a natural reaction by the plants to slow transpiration, so doesn’t necessarily mean that the plant is water-starved. Dig a little hole and see if the soil is really dry before getting worried.
So the answer to my question obviously depends on what I’m watering (mature plants with deep roots – or not), when the bed was watered or rained on last, and the forecast for rain or watering. Therefore my rule of thumb will be never more than 10 minutes on any one bed, usually probably only a few minutes – especially if the soil is already moist a few inches down – and maybe slack off a bit on the tomatoes.
Comments?
First Run of Michael Prager’s Cool Compost Sifter (aka “trommel”)
Q: How fast does a zucchini grow? (Redux)
(This is a repeat of an earlier experiment from July 2017.)
A: About 1 inch per day – same as in 2017.
