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hosenemesis

Root Knot Nematode Photo

hosenemesis
12 years ago

Hi all,

If your veggies look thirsty and you think they are getting plenty of water, you may have Root Knot Nematodes. This is what the roots of the plants will look like if you dig them up. These are pattypan squash roots:

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All of the beds in my lovely little four-year-old potager are now infested with this tiny beast, and there is no way to eliminate them (legally, anyway). They favor the same plants I favor: heirloom tomatoes, squash, cukes, eggplants.

I highly recommend growing these vegetables from seed rather than taking the risk of importing them with nursery starts. There are nematode-resistant varieties of tomato and pepper, and Tomatomania reports their first success with grafted tomato plants, so that may be an option in the future if you prefer the taste of the heirlooms. Keep in mind that nematode-resistant does not mean nematode-immune. There are winter veggies that are resistant as well. Good gardening luck to all of you!

Renee

Comments (5)

  • sautesmom Sacramento
    12 years ago

    Also, I have noticed a VAST improvement in all plants if you mulch heavily. I have noticed squash leaves are easily 2 to 3 TIMES bigger simply because you have mulched all the soil around the plant, keeping it cooler and encouraging healthy soil. The less stress on the roots, the better they can deal with being compromised by nematodes!

    I first put down my drip hoses, then I put newspaper or cardboard, then six inches (at least) of oat straw or organic grass clippings (if getting donated clippings, make SURE your neighbors do not use any lawn supplements other than manure. Many people don't realize "weed n feed" consists of pesticides/herbicides, and you don't want your tomatoes or YOU to be eating herbicides!)

    Try mulching on one plant and one plant without--you will be amazed at the difference, especially if you have nematodes!

    Carla in Sac

  • jean001a
    12 years ago

    When your beds are infested with nematodes, the key is to use tolerant plants as has been suggested.

    Further, install sizable transplants rather than seed directly into the beds. The younger the plant when it is when first attacked, the shorter its lifespan will be.

    Jean
    who gardened in nematode-infested beds in SoCal thanks to a free tomato transplant obtained at a garden club meeting.

  • hosenemesis
    Original Author
    12 years ago

    Jean, how fast did the infestation spread? Did it affect your ornamental plants as well?

    Good advice, Carla. I got a dozen squash before the poor thing expired, and it was probably because of the mulch. I only got a few Mortgage Lifter tomatoes, and Stupice is just now showing signs of stress, and I have been eating them for about a month.

    Renee

  • socal23
    12 years ago

    Root knot nematodes don't spread very fast if at all naturally. Almost all spread is due to poor sanitation (spread by gardening implements and infected materials).

    Additionally, there are plants that produce root exudates that are toxic to root knot nematodes (broccoli) and many species that they simply won't use. 2 - 3 years of toxic/ unpalatable plants will effectively eliminate them - but remember to control weeds - alternate food source.

    Ryan

  • jean001a
    12 years ago

    As socal says, they spread very little on their own.

    My infestation spread quite rapidly because I was making new beds from old but didn't yet know I had a problem. Ack!

    Yes, they affect ornamentals. But just as with veggies, not all.

    Once you know you have nemas, it wise to be extremely careful about what you do & how you do it.

    Some suggestions:
    - deal with infested sites as the last task of the day
    - and if possible with their own set of tools
    - clean your shoes/boots well after you leave an infested area.
    - never, ever, move plants from an infested area to another site, even though their roots look fine because the nemas are in the soil around the roots.
    - never set a pot on infested soil, then move it to clean soil -- the nemas can hitch-hike
    - perhaps have a separate hose for the infested area rather than drag the soil to clean areas.

    And each season, mix in lots of compost, 3 inches or so. The compost aids the populations of beneficial soil organisms which help limit the nasty nemas.