Return to the California Gardening Forum
| Post a Follow-Up
Root knot nematodes - do you have them
| | |
Posted by socalgal z10CA Sunset z24 (My Page) on Mon, Nov 2, 09 at 10:19
| I have discovered root knot nematodes in three different areas of my garden (on tomato roots - although the tomatoes actually grew quite well). How common are these in Southern California? Are they probably all over my garden? |
Follow-Up Postings:
RE: Root knot nematodes - do you have them
| | |
- Posted by bahia SF Bay Area (My Page) on
Mon, Nov 2, 09 at 11:34
| They probably are all over the garden, but they don't really bother most plants to any significant degree. As you discovered, tomatoes are one target, marguerite daisies are another favorite target, as are chrysanthemums in general. There are biological controls that you can buy at a better retail nursery to keep them in check, maybe you should check with your local county agricultural agency to see what they recommend in your area, as well as local sources. For the tomatoes, it is probably best to switch around where you grow them each year, or the problem will get worse next year, also only plant resistant varieties if they can be had in your area. |
RE: Root knot nematodes - do you have them
| | |
- Posted by jean001 z8aPortland, OR (My Page) on
Mon, Nov 2, 09 at 13:04
| It was said "...but they don't really bother most plants to any significant degree. " Umm, sorry. Not so if the plants are susceptible -- among veggies, that includes tomatoes, peppers, beans, cukes & more. The affected plants won't be as vigorous, nor as productive, nor as long-lived as they should be. One counteracts the problem by starting with healthy transplants not from seed sown directly into the garden. And use kinds of tomatoes with the "N" following their name -- you know, the entire list of possibles is VFFNT. Then too, always mix at least 2 inches of compost into the bed before you plant. Jean,
who gardened in Long Beach, CA, for 30-some years and continuously fought the nematodes all the while |
RE: Root knot nematodes - do you have them
| | |
| I did an experiment with tomatoes and nematodes this year in 2 raised beds. Each was on a drip line, heavily mulched, and planted with Black Cherry, which is well suited to the coast. Both reused the soil from last year, whose nematodes killed the tomato plants by end of summer. One bed was topped with the entire contents of my worm bin - about 3-4 gallons of worm poop. Results: bin without worms - dead plant by August; bin with worms - still producing tomatoes in November. It isn't practical to find a new spot or replace the soil every year, so I'm going to try this again next year, especially since worm bins are so cheap to make. =^,,^= Diana |
RE: Root knot nematodes - do you have them
| | |
I got them this year in my cucumbers. I believe they have only affected one bed, so I am leaving it fallow this year. If the bed has problems the following year, I'm going to dig the soil out and start a compost pile in that spot.
Renee |
RE: Root knot nematodes - do you have them
| | |
- Posted by jean001 z8aPortland, OR (My Page) on
Tue, Nov 3, 09 at 10:50
| hose said " If the bed has problems the following year, I'm going to dig the soil out and start a compost pile in that spot." I suggest you re-think that plan. If you do that, I'd be concerned that you'd contaminate the compost and end up spreading the nemas all over he place Instead, I'd reserve the affected bed for things that nemas don't bother. Or, what I did while in SoCal because my space was so limited, was to heavily amend -- mix in 2 inches or more of compost each time I planted the bed -- to increase the natural predators of those plant-damaging nemas.
|
RE: Root knot nematodes - do you have them
| | |
| I know I have them, I don't give any plants away that I have grown in open run. I use blech on the soil. Tomatoes, I grow them in pots. Onions I just put in pots. Herbs go into pots, I toss soapy dishwater onto the ground, any water I cooked in goes out to water the plants, My plants are grown so closs in the border to hold back the weeds, and this is topped with gravel and rocks. I have lots of Hummingbirds, squirrels, racoons, and oppossum, ants, grubs, etc. just like any over garden, less bees this year which has me worried. Lots of cats visit plenty of rats for them to eat. Normal Garden. and of course the nematodes. Norma |
RE: Root knot nematodes - do you have them
| | |
Marigolds aren't a 100% fix but their performance was pretty impressive in a study that is currently being conducted by Antoon Ploeg; a nematologist and UC Riverside.
I was at a UC research field day about a month ago and he was showing off his latest study. Planting French marigolds before tomatoes was giving control similar to commercial nematicides.
When the marigold roots are penetrated, their response is to produce chemicals that kill nematodes. The one that's most likely to have this effect is called "α-therthienyl". Here is a link to a study that goes into the process in painful detail.
You have to plant them though. Marigold tea and other stuff won't work because the roots have to be present and then be attacked for the chemical to be produced.
For tons more nematode information from a local extension guy, check out his site and links
His study also included some of the resistant varieties that Jean was talking about and they were performing much better than other varieties. When the resistant varieties were planted after marigolds, the plant vigor and production was very near that of the control group.
Then too, always mix at least 2 inches of compost into the bed before you plant. is also good advice since it helps increase the population of beneficial bacteria, fungi and predator nematodes that aid in control. |
Post a Follow-Up
Please Note: Only registered members are able to post messages to this forum. If you are a member, please log in. If you aren't yet a member, join now!
Return to the California Gardening Forum
|
|
|
