I am looking for some advice on pest prevention for container plants, particularly slugs, caterpillars, and ants.
My very urban deck garden is strangely large for a 4th floor walkup, blocked by large buildings on the south and west, but gets great morning sun and dappled light all afternoon. Quite luscious for Manhattan on a low budget - I have decorated it well - including a little fountain - and have many different plants in about 30 containers ranging from 12-30", and plants range from bleeding hearts to Endless Summer hydrangeas to fuschias, hosta, coleus, many annuals, and - new for me - trailing annuals in containers on the wooden ledges. A country garden in the city! I do ok with the gardening part on my own (read forums, talk to mom in the south, and trust Mother Nature to tell me what works 500 feet above the ground on the Upper West Side and what doesn't), but I get plagued by pests that somehow manage to get up here! Either they are climbing up 500 feet from the street, or they are falling from the trees above? I have no idea, but I would like to take preventative measures this year.
Slugs and caterpillars have tried to eat my plants up over the past two years. One hot year, one rainy year. For the slugs, I put out poison pellets, but it took a while to work. For the caterpillars, I asked my neighborhood store, and they advised a spray that smelled like "death" to all, I could hardly stand the stench of it, and my neighbors are 2 feet away. In both cases, I could not figure out how the little buggers got up here, as I had barely seen a bug in the 3 years before...maybe a few bumblebees and moths, which I was happy to see alive in what is essentially an alley with some crappy yards very,very far below. My deck is wood, so maybe they are living underneath, in the space between my deck and the roof of the apt below? Are they falling from the trees above (which manage to live sandwiched between 20-story buildings?) And now I have ants...in the house, I think I rescued a plant that looked ok but maybe had ants living in the bottom of the container, I picked up a container today that had not been touched since last fall, as I was potting the newbies and 10000 ants ran out...
Anyway, I am looking for some advice on pest prevention for container plants, particularly slugs, caterpillars, and ants. and would appreciate ideas that do not involve smelly sprays, as my neighbors are literally 12 feet above me!
Thanks, and thanks for all of the excellent advice provided on these forums!
SS
city container gardener needs pest prevention help, please
I work at a small nursery, and we put about a 1/2 inch thick layer of sand on top of the soil for the potted hostas. Since you're going to be watering everyday anyway, you might want to try that- it really seems to work well. At home I put a goodly handful of crushed egg shells at the base of my plants in my pots too.
Are your pots directly on the deck? Your slugs are also probably hiding under your pots during the day and coming out when it's cool at night. You might try raising them up on "pot feet" to get air circulation/dryness under there. Or tip and check daily. It is odd that you have these problems so high up! But slugs need damp and a place to hide during the heat of the day- eliminate those variables, and you'll have a good start.
Ants like dry- in fact, they can't swim, and won't try to cross water. So if you find them in one of your pots, soak it in a bucket of water. Icky, but they'll drown. If they keep coming back, it's because the "scouts" have left a chemical trail for their fellow ants to follow- a scrub with a 10% bleach solution wipes that out. Every time you see an ant, kill it and swab the decks-eventually they'll stop coming.
I dunno about the caterpillars- I let them do their thing at my place, but if they're being really damaging, I can't blame you for wanting them gone. Trouble is, most caterpillar sprays are bad for bees, butterflies, and other good bugs. Pick and toss overboard would be one solution! Or designate a "caterpillar zone" and let them eat and do their thing.
Maybe others have some insights too-?
Good luck!
SS
Nedweenie is on track with everything but the ants. I'm sure I read something about ants and being able to be in/under water for a few days. Maybe someone else can confirm. I know that with my lymphoma I stay away from chemicals and try the earthy things.
I also have mixed cayane( I'm not sure of the spelling)pepper and cornstarch and sprinkle it along their trails, some folks mix borax( washing kind) and icing sugar as they take it back to their home and in cleaning them selves ingest the borax and it does them in. Maybe you could try a sticky trap on the floor to catch them too.
I also pick the catapillers.
Even if you have to share a bit you will still enjoy your garden!
Ann
Something I've written about neem oil. It is extremely safe & very effective. Please read:
Neem Extract as an Insecticide
In India mainly, but also Asia and Africa, grows a tree all plant enthusiasts should be aware of, Azadirachta indica, commonly known as the "neem" tree, and a relative of mahogany. Extracts from the tree’s seeds contain azadirachtin, a relatively safe and effective naturally occurring organic insecticide. Let me preface the comments following, by reminding you that the terms "naturally occurring and/or organic" do not universally mean safe. Pyrethrums, rotenone, and even the very dangerous nicotine are all organic insecticides that should be handled with great caution. Neem extracts, on the other hand are very safely used in a wide variety of cosmetics, as a topical treatment for minor wounds, as an insecticide in grain storage containers, bins, and bags, and a whole host of other applications, and have extremely low mammalian toxicity. I'll limit this discussion to its use as an insecticide.
Neem works in many ways. It is effective both in topical and a systemic applications. It is an anti-feedant, an oviposition deterrent (anti-egg laying), a growth inhibitor, a mating disrupter, and a chemosterilizer. Azadirachtin, a tetranortriterpenoid compound, closely mimics the hormone Edison, which is necessary for reproduction in insects. When present, it takes the place of the real hormone and thus disrupts not only the feeding process, but the metamorphic transition as well, disrupting molting. It interferes with the formation of chitin (insect "skin") and stops pupation in larvae, thus short-circuiting the insect life cycle. It also inhibits flight ability, helping stop insect spread geographically
Tests have shown that azadirachtin is effective in some cases at concentrations as low as 1 ppm, but some producers use alcohol in the extraction of neem oil from plant parts which causes the azadirachtin to be removed from the oil. Some products touting neem oil as an ingredient actually have no measurable amounts of azadiractin. I use what is referred to either as cold pressed or virgin neem oil. You may also occasionally find it referred to as "raw" neem or "crude" neem oil.
Neem oil is most often used in an aqueous (water) suspension as a foliar spray or soil drench. Commonly, it is diluted to about a .5 to 2% solution, but the suggested ratio for use in container plant culture is 1 tsp. per quart of warm water. A drop or two of dish soap (castile or olive oil soap is best) helps keep the oil emulsified. The mixture is then applied as a mist to all leaf and bark surfaces and as a soil drench to the tree's root system. It should not be applied as a foliar spray on hot days or in bright sun as leaf burn may occur. Remember to agitate the container frequently as you apply and do not mix anymore than you will use in one day. Neem breaks down rapidly in water and/ or sunlight.
Some users of insecticides feel the need to observe the instant results of their efforts in order to be convinced of the effectiveness of what they are using. The application of neem derivatives does not provide this immediate gratification. There is virtually no knockdown (instant death) factor associated with its use. Insects ingesting or contacting neem usually take about 3 - 14 days to die. Its greatest benefit; however, is in preventing the occurrence of future generations. It is also interesting to note that in studies it was found that when doses were given, purposefully insufficient to cause death or complete disruption of the metamorphic cycle, up to 30 surviving generations showed virtually no resistance/ immunity to normal lethal doses, so it appears that insects build no ‘resistance’ to azadiractin.
I have been using neem oil for five years as both a preventative and fixative and have had no insect problems on my container plants. Applications of cold-pressed neem oil are most effective for use on mites, whitefly, aphids, thrips, fungus gnats, caterpillars, beetles, mealy bugs, leaf miners, g-moth, and others. It seems to be fairly specific in attacking insects with piercing or rasping mouth parts. Since these are the pests that feed on plant tissues, they are our main target species. Unless beneficial like spiders, lady beetles, certain wasps, etc., come in direct contact with spray, it does little to diminish their numbers.
Neem oil does have an odor that might be described as similar to that of an old onion, so you may wish to test it first, if you intend to use it indoors. I've found the odor dissipates in a day or two. As always, read and follow label instructions carefully.
Neem oil can be purchased from many net or local sources. My favorite brand is Dyna-Gro pure neem oil. If you have trouble locating a source, you can contact me via the forum or directly.
Al Fassezke
Thanks for the advice, and I think that nedweenie called the problem - there is a 6" gap between my high-up deck and the roof below, so there is a place for buggers to hide no matter what I do...and there are several trees that drop lots of leaves that have seeds in them, which turn into many weeds on this high level deck, so it is more like a yard in that way. I cleaned out the probably rotted leaved under the built-in ledges - but there are years more of accumulation, I bet... (The guy who built the deck clearly never sat out on it!) so hope that will help, but I foresee caterpillars, which were surprising large for 100" square feet of space (many, many plants, but like a magazine pic, so nothing unusual)...I sprayed the stinky spray and would see them running out of ...where??? maybe need to put all pots on bricks or something. But I will also get the Neem Extract.
Thanks and will post pics soon!
SS