Hello. I just finished pulling out all my nasturtiums, as I do every year about this time, because of those yukky black bugs that appear and smother them every year. In the process, seeds drop all over the place, and I will soon have a new crop. I have always assumed these bugs are aphids. I don't bother to treat them with pesticides because 1) I don't like pesticides, 2) the aphids are relentless in their pursuit, and 3) the nasturtiums replace themselves with no effort on my part. I don't think I've ever heard any myths about nasturtiums keeping away bugs; be assured they don't. If you just planted your nasturtiums, you are very late to the party, they perform best as a spring bloomer in my garden, although I will get a smaller, less vigorous bunch in summer. Now one should be planting hot-weather bloomers from 6-paks, (a bit late for seed) such as zinnias, vinca, portulaca, petunias, etc.
Good luck!

You are experiencing first hand all the ins and outs of companion planting regarding pests. Nasturtiums are generally thought of as a sacrificial plant for some pests, at least they are here.
I'm not sure I can help you to control the black things without more info on what they are, but as far as the green caterpillar, I do know that they are probably a looper (we call them inchworms) and in the "pests and diseases" forum I'm getting clarification on the differences between a cabbage LOOPER and a cabbage WORM. They look identical to me, but apparently the looper has either two more or two less prolegs than the worm. Frankly, they look the same, act the same, and eat the same. I don't see what the big deal is, but Venus must be in the ninth house or whatever 'cause there has been much hairsplitting lately. LOLOLOL!! So, *speaking into my wristwatch phone*, Loopers are bad. Kill 'em all. I used parasitic wasps to control mine this year after battling them for three years. They are future moths, which are repelled by curry plant, which I planted this year and seems to be working. Hope this helps. >:)

Yep, as Greengoddess explained the nasturium is good for keeping bugs off it's companions by acting as a trap crop.

Black things are most likely aphids. If you want some nasturtiums to consume (very nice peppery flavor) plant another crop farther away from your veggie bed. Everything I have read about Nasturtiums lists them as a trap crop. They keep the aphids, worms and a few beatles off your veggies by giving them something more attractive to munch on. When they get invested, diggem up, shred em and throw em on the compost heap. Assuming you have a hot compost heap any eggs/larva/etc. should get toasted.

I had (maybe still have) a black bug problem with some nasturtiums I planted along a chain link fence in the front of my yard. I don't know if these are the same thing since these were about a sixteenth of an inch long, but there were plenty of them on each leaf. I might point out that the nasturtiums were part of a "climbing plant mixture" I purchased to cover up the fence -- the package also had morning glories, cardinal climbers, thunbergia black-eyed susans and sweet pea. An couple of hours ago I sprayed the leaves with 1 tbsp liquid dish soap and 1/4 cup amonia and water in a small sprayer. They didn't like it at all (what a shame, since they were devouring the leaves) and most quickly jumped to other plants although they don't seem to be eating the others. A few minutes ago I went out and at first thought they had come back to the nasturtiums but everyone that was on the leaves was dead. I can't imagine that a dilute mixture of soap and amonia (which after all is just nitrogen) would hurt the plant, although for safety sake maybe I'd better wait a few days and see. As such, I can't recommend doing this, but it was an action which brought a certain sinister satisfaction when I saw how many had died. Heh-heh-heh.

oh, my you are a livly group. I've been too long on the other forums, didn't know what I was missing...there's a lot of action here! The soap is a wonderful aphid weapon, I don't know about ammonia, but I don't think you'll be eating any nastursium blossoms that were sprayed with that! I'm thinking the black can also be the eggs of the moth that brings cabbage worms, seen them meny times tucked in the leaves of the cabbage, "nasty" always seemed the term for that discovery. Keeping the moths off your nastursiums may be a real difficult task, sometimes you have to get them at another stage of development,ie egg or larva/worm.

Wow, that's interesting. A trap crop! Makes sense since nasturtiums are around for such a short period. I love how they self-seed. Has anyone had the same success with Johnny-Jump-Ups? I used to have them all over the place, but now, :~( none!

And the black COULD be FRASS (caterpillar poop)

**Macca**

Hi-I recently read a book on organic gardening that said there is a big difference in companion planting properites between orange naturtiums and yellow nasturtiums.

One sort is insect repellent and the other a 'trap crop' that attracts caterpillars and butterflies away from your veges... I think the orange ones are the trap crop, and the yellow ones insect repellent.
Now if someone can explain why I have aphids and white fly on my basil - which is supposed to be a good companion plant for tomatoes- for it's abilities to repel, sigh, aphids and white fly...

I don't have nasturtiums but try planting some onion or garlic or both with them. With my tomatoes this year I planted onion ,leeks,chives,carrots,basil,oregano and borage and I gota be honest with ya, the only bugs I seen were bees, wasps and butterflies on the borage. Don't be afrade to experiment! If you do have aphids on nasturtims could be a lime deficiency in the soil.

I live in Oregon and have the same problem with the little tiny black bugs (they look like pepper). So far they are only on the plants I had in containers, the others in the flower bed are pest free so far. I moved the potted ones far from anything else but I am watering and caring for them to let them be little sacrificial lambs for my other plants. I would be interested in knowing what these bugs are though and if there is anything I can do to prevent them.

I have the black bugs too, or rather, my nasturtiums do. They are bugs, for sure... They crawl. I have mine below my Madrona for color, and the Madrona is dropping its leaves like crazy right now. I was just crawling around on the ground to clear out the leves, and the bugs are so prolific it's like the leaves and stems are covered with dirt. I want to take a shower before working on any other part of the garden! LOL
I picked up a pack of seeds for ten dollars at Home Depot and scattered them below the tree, the results being many colors of flower. It's pretty, and the plants are acting more like vines and laying all over the ground, but the bugs are definitely NASTY. No other plant in my yard has such a huge number of pests on it. I guess I'll try the soapy solution and see what happens.
I would be happy for any more information on these bugs!

OK, it's been two years since the last post, and no one yet has identified those tiny black pests. A horde of them just appeared on MY nasturtiums, so I'm renewing this thread in hopes someone can put a name to them.

I just found these nasty little black aphids on my nasturtiums too and they are going to town! See below for info that I found on another site and click on link for more details at that site.

"Widely grown as companion plants, nasturtiums are one of the gardener's best friends because they fend off garden pests from neighboring plants. Grow them near squash to help repel cucumber beetles, and they will also help keep away many different kinds of aphids. Though they do attract one species of aphid, the black aphid, you can use this to your advantage. If black aphids are a problem, grow nasturtiums to keep aphids from destroying other plants. Then when the nasturtiums are covered in aphids, pull those plants up and destroy them, aphids and all."

Here is a link that might be useful: Nasturtium Info from Flower & Garden Magazine 1999

In 2011, and for the first time, nasturtiums that I hung in a pot picked up something black that could have been an aphid. There were so many of them that it would have been difficult to find some not-infested leaf to eat. It was late summer (and at that time I did not know that summer would last until late November) so I just let the bugs have their way. They got very thick as all the weeks passed that I was sure would be the last before frost (which we usually get here in September).

As a side note, why is it that everyone (seems to) know that the flowers are edible but seem to not know that the leaves have pretty much the same flavor? I use the leaves constantly in salads and in cooking.

So, I have just started a new crop for this year: 4 types from Johnny's Seeds: Peach Melba, Night & Day, Empress of India, Kaleidoscope. I just noticed what looks to be white fly. I put some Sticky Traps from Safer's near the plants. I have some basil that may be affected and I have 9 varieties of tomatoes coming up. It is too cold to move the tomatoes outside and I do not want them infested.

So, even though nasturtiums are specifically stated on the label of Safer's Soap as "do not use [soap on nasturtiums]", I took most of them outside, sprayed them with Safer's Soap (and some liquid seaweed), and came here.

Our nasturtiums have the little black aphids as well, but not every plant is equally covered -- the aphids seem to prefer just certain flowers, so I went outside to check if color made a difference (we planted gold, orange, and red nasturtiums this year). I found the most aphids on the stems of the gold flowers, but there were also aphids on some of the red and orange flowers as well. The section of the garden with more shade had a higher number of infested plants, but on whole only about 10% of the plants were infested. They seem to be keeping aphids off my vegetable garden, as that hasn't been a problem this year, and possibly attracting beneficials, as I did see one ladybug earlier this summer (which is better than zero). We plant from seed every spring, and they seem very happy in our Pacific NorthWest weather, but eventually die off in Fall. In California, they're perennial.