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growsy

help for planting a Black Swallowtail cat host plant bed

growsy
11 years ago

Hi! I've had a little bit of a conversation with Terrene on the wintersowing forum about how we had a bunch of Black Swallowtails at our house last year. They laid a bunch of eggs on the 2 parsley plants I had. After stripping the parsley they moved on to the other plants in the bed & ate the leaves off the peppers & two small tomato plants. The bed & the ground around it was crawling with them. This year I want to be prepared - but I don't want to use the space in my small veggie beds.

The best spot I can find is this patch between the flower garden & the shed. It is sand (SAND). :) The tree is a tall spindly oak which gives the space afternoon shade, & fills the sand with roots.

I have 2 straw bales & I was thinking I could plant in those, but it won't give me a lot of room. However, whatever I do has to be on the cheap because there just isn't a budget for this. The other option is to just plant into that sand, maybe mixing in a bag of compost & working around the roots. (For reference, the bed the cats over-ran was 4'x4'. I don't think many of them made it because there wasn't enough of their food. We only saw one cocoon before I had everyone stop walking in the area because there were so many cats on the ground. Then we had some other things going on & I didn't pay attention.)

The 2 parsley plants recovered & I'm hoping I can move them. I've wintersown parsley (only have 2 sprouts so far) ammi majus (13 sprouts), dill (3 sprouts - there were more but I lost some - this is my first time wintersowing). I also have carrot seed. I can also probably purchase a few plants later in the season if I need to, but I'd like to get my plants going now so they have some size on them before the cats arrive.

Anyhow, all that to ask - do you have any suggestions? Should I plant what I can in the straw bales, or have you had any luck growing these plants in poor sandy soil? I can fit more plants in if I plant into the ground, but they might not do as well as in garden soil or compost in the bales. I'd be happy to have suggestions because I'm tired of chasing this around! Thank you!

Comments (11)

  • molanic
    11 years ago

    Wow, that must have been some sight with all those caterpillars! I'm surprised the birds didn't make a buffet out of them or that wasps didn't get them. I rarely find a mature caterpillar in the garden for those reasons. I always have to go searching for eggs or sometimes tiny cats in order to raise any.

    I don't have any experience with sandy soil because mine is more clay based. But I know dill and parsley tolerate dry soil pretty well...at least up here in zone 5. If you've got enough seed I would try in the bales or containers and the ground as well to see what works best for you.

    Bronze fennel is probably my best performing host plant for black swallowtails. It gets huge 4-5', bushy too, and doesn't need any soil amendments or extra water. It has come back for several years and will also produce many volunteers unless you dead head it. All of these plants: fennel, dill, carrots, and parsley are excellent to interplant in a veggie garden because their flowers attract lots of beneficial insects. Some of these will kill the black swallowtail cats unfortunately, but they also take care of the insects that can damage your veggie plants.

    In general it is easier to keep things from drying out if planted in the ground rather than containers. But the benefit of containers is that if that location doesn't work well, you can move the containers to more or less sun.

    All those plants also self-seed quite a bit so once you get some going you should have a nice stand for years to come.

  • docmom_gw
    11 years ago

    I would plant directly into the ground. I also agree with the comments on fennel. I would throw down dill seeds and fennel seeds and water gently until they have some size on them. Good luck. I hope you get as many visitors as you did last year.

    Martha

  • growsy
    Original Author
    11 years ago

    Thank you! I do have some fennel seed I haven't started yet. No Bronze, unfortunately, but maybe I can pick some up. I itch to get started then I get so many "what-ifs" & "what-abouts" swirling around in my head I get stuck. It helps a lot to have feedback from others!

  • Tony G
    11 years ago

    common rue (Ruta graveolens) attracts both black & giant swallowtails and the foliage is beautiful.

    I like bronze fennel but its also a wasp magnet. If you want your caterpillars to stay "under the radar" parsley, carrots, and rue are good choices.

    Good luck! Tony

  • growsy
    Original Author
    11 years ago

    I am going to have to get some rue for next year. Thank you Tony. I'd never heard that bronze fennel attracted wasps!

    I decided not to use the straw bales & I did move the 2 parsley plants. I planted 5 lupine along the back & then covered the ground with a mix of carrot, fennel, dill, & parsley seed (with a few more lupine seeds thrown in). Some of the seed is pretty old, but there should have been plenty new to get a good cover. Then I spread peat moss over that. The first day I kept it wet - then yesterday we had a light rain all day long. I'm looking forward to seeing sprouts!

  • Tony G
    11 years ago

    Growsy,

    the wasps aren't aggressive toward me, but they feed on the caterpillars. The fennel seems to attract the most egg laying though....at least up north! Hopefully someone in your zone will chime in too.

    To save a few caterpillars from predators, I pot some parsley in late summer and raise a final batch indoors. They stay in my 3 season porch all winter (as chysalises) and then hatch in spring. Tony

  • molanic
    11 years ago

    I have found that the flowers of all the plants in the carrot family attract large numbers of insects including many types of wasps and hover flies, tiny beetles, etc. If you let the parsley and carrots flower in their second year they will be insect magnets too. In my yard the fennel, parsley, and goldenrod flowers attract the greatest number and variety of insects by far. It is fascinating to watch the swarm surrounding them when they are at their peak. If the swarm bothers you, but you still want the foliage for the caterpillars just cut off the flower stalks. The rue flowers are not as busy and it seems to be a last choice as far as black swallowtail eggs at least here. It is an attractive plant though and may get giant swallowtails to lay on it as well. Be careful when working with it though because it may cause some light sensitive skin blistering in people.

    I would make sure that the peat moss never dries out until the seedlings get a good start because once it dries out it is pretty hard to re-wet.

  • Tony G
    11 years ago

    good point molanic, I always grow parsley as an annual so I haven't had increased insect traffic because of flowering.

    Garden gloves are always a good idea to avoid allergic reactions...I like the atlas ones because they're thin and they dry out fast

  • madabouteu
    11 years ago

    It has been my experience that fennel is by far the most attractive host plant for this species of butterfly! I have big problems with aphids on dill, and the butterflies ignore carrots and parsley if fennel is around.

  • joraines
    11 years ago

    The bronze fennel in my butterfly garden. I also have parsely and dill but see the cats on the fennel about every time I look.

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  • Leafhead
    11 years ago

    Fennel definitely gives you the most bang for your buck.
    I got 29 cats off just one plant Summer before last...
    I'll have to try some Bronze this year and see what happens...

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