Catastrophic Failure: Broccoli

[David Taylor]

But not just broccoli, every kind of cabbage family fails me. Years ago I'd get large heads of cabbage, but now all I get is leaves with stalks between them, broccoli with no heads to speak of, Brussels Sprouts that just don't head up. This last batch was over the winter, under cover. The soil is clayish, as is most soil is SoCal, but after twenty years, the soil is also much more friable than the average. I've slowly dumped in sand and humus to make it better soil, but I had better luck fifteen years ago than now, when it comes to cabbage family plants. Any suggestions?

[The Helpful Gardener]

Rooting issues? Any lumpy misshapen roots?

Couple of fungal issues focus on that family...

http://www.omafra.gov.on.ca/english/crops/facts/85-043.htm

Anything jump out?

HG

[David Taylor]

HG,

Lot's of good info at this site, and I'm going to have to digest it, but at first glance, nothing really does jump out.

But y'know what I'm gonna do? I'm gonna trot right down there while I have some light and pull broc up and take a gander. Get back to you. Thanks for the input.

[David Taylor]

Went down and pulled up a brocolli plant. The roots themselves looked good, but there is very little of the the big thick root, and a whole lot of dense, vigorous hair root. No maggot worms or critters that I can see with the naked eye, no shedding, no rot. Certainly nothing like the tomato nematode roots I've seen (that has permanently traumatized me.) Looking at the pictures at the above site, I just don't see anything even remotely similar. These are real bad cases of fungal infection, aren't they?

[The Helpful Gardener]

Yeah that's the tendency of these images, to pull worst case scenarios instead of "This is what it looks like right before all your plants croak." Go figure...

You mentioned sand and humus, but what about compost? It may be that establising some better biology in the soil may be beneficial (either competing with bad biology, or providing services for the plants that were lacking). Might help...

HG

[David Taylor]

That's certainly worth a try. I might try throwing in more amendments, like blood meal, something with a high nitrogen content. My experience has been anything where you eat the plant, like lettuce, and not the fruit of the plant, usually loves a lot of nitrogen. Cucumbers and peppers, tomatoes, they're trickier, but I'm getting those. Corn, of course is an exception.

Really do appreciate you help. Thanks.

[applestar]

This might be a REALLY dumb idea, but I'll throw it in just in case
Is your garden in an open space? Because trees and things can grow up over the years and cast much more shade than there used to be in a given area.

My Veg garden beds are slowly migrating towards the front of the house (they're all along the side yard now. In another 5 years, who knows?) because the trees in wooded area behind the back fence cast longer shadows every year. There's a dense shade where I used to grow tomatoes years ago when I first moved into this house.

[The Helpful Gardener]

Actually you can shut down fruit production with too much nitrogen (seen it happen dozens of times where lawn fertilizers get into veggie beds). PLants only friut to reproduce and if the plant thinks it's on the gravy train, not so much reason to reproduce. Balanced ferts (like Bradfield Organics 5-5-5 for veggies) are more recommended...

HG

[rtruitt]

I had similar things going on and my brocolli would rarely head up. I am in a new garden area with very low fertility so I boosted my organic nitrogen and added a little turkey compost and BOOM... 8-12 inch heads. I was extremly pleased.

Weather can also play a big part but since you seem to be having a multi-year issue soil fertility seems to be the culprit.

Good luck.

[The Helpful Gardener]

Ron, what did you do to boost organic N (other than the turkey compost...)?

HG

[pharmerphil]

I would say it's nutrient lock up (check soil Ph)
causing a trace element deficiency
requirements: pH of 6.0 to 7.0
Brassicas do best in cool weather, but that time of the year, microbial activity, soil activity and the availability of trace elements are lessened. they require certain trace elements in moderate amounts. they require molybdenum and iron Ph has much to do with these micro-nutrients due to the fact that most trace elements become less available as the pH of a soil rises.

[The Helpful Gardener]

Howdy pharmerphil!

What nutrient do you think is locked up? Sounds like you think it's micronutritional deficiencies... What do you think is raising ph?

HG

[pharmerphil]

most all micros, can be locked up, with a Ph imbalance, the exception being molybdenum, brassicas need boron manganese molybdenum and iron.

As for what could be effecting the Ph. I would suspect soil drainage, beings as it was stated to be clay soil.
even with amendments (our soil is high in clay, with a organic content of over 6%) typically, clay soil is alkaline (has a high pH)
and even though it has been amended, clay particles, after years of watering/rain and foot/machine traffic...will settle and bind together, effecting drainage, maybe not within the top 6-8 inches, but beyond that, in the root zone of most deep rooted crops, it can get very heavy

[The Helpful Gardener]

Phil how about using a fungal compost to stimulate a weak acid response? Fungus tends towards acids, bacteria tends toward base... Might you be an organic farmer?

HG

[David Taylor]

According to my notes, the Ph was 6.8 when I first planted the plot (Just in passing, I planted New Zealand Spinach in the same plot, and have fresh stuff constantly, as well as having canned a dozen pints, with no break in growth showing). I also double-dig my plots once a year, and they end up raised. This particular plot is about six inches tall, six by four feet.

I thought we were all organic, here.

I will go down an check the Ph, but probably tomorrow will be the soonest I can get to it. one of The Progeny is in a play this evening.

I really do appreciate the in-put.

[The Helpful Gardener]

6.8 pretty much rules out a micro lock-up; everything is pretty available at that point... still the micros for brasssicas aren't exactly the same as spinach... how many years ago was that 6.8 and what have you been adding since?

Could be a nitrogen deficiency; highly bacterial soils can lock nitrogen up IN the bacteria ( they are nitrogen rich with a C:N of 5:1). Moving things towards fungal can unlock all sorts of goodies; calcium 'frinstance, or potassium (which unlocks a little better back around 6.0. Introduciing protozoans would start a poop loop with the bacteria and stimulate some weak acid response, which would boost fungal side. Adding compost almost always makes sense for one thing or another, and it almost never hurts. I'd topdress with good compost. The beauty of natural systems is they are always striving for balance, which is pretty much where we want to go, so adding biology will start to unlock all the nutrient we need. If it is bacterial nitrogen deficiency, the best thing we can do is introduce predators...

HG

[pharmerphil]

Phil how about using a fungal compost to stimulate a weak acid response? Fungus tends towards acids, bacteria tends toward base... Might you be an organic farmer?

HG

That's a possibility, sorry for the absence, weathers been good, ..no, just an organic gardener HG

[kabrina2]

One of my gardening books suggests if the broccoli does not have heads that it could be a calcium deficiency corrected by limestone tilled in for the following season or improper watering. It suggests a minimum of 1" of water a week.