Broccoli leaves Turning Bright yellow then dieing off and falling off the stem?

I am alarmed..to say the least I had the world's most beautiful broccoli growing this year...absolutely gorgeous until the last week. We had a run of 100 degree days (most unusual here in Minnesota)--record temps! Broke 100 year temp records here and all of a sudden my beautiful gorgeous broccoli plants (just at the point of producing their first big heads) have the bottom leaves turning a bright yellow and then dieing altogether and falling off the plant stem. I am panicking...needless to say!!! Can someone help me out here?

I read in my "problem solving" book from Rodale's a number of problems that all involve the oldest leaves suddenly turning yellow and dropping off the plant stem--and really would have a tough time figuring out which problem I am dealing with? One other "hint" is that we also had a period of "torrential" rainfall (I think we had 5 to 8 inches of rain PER DAY for a week and a half right before the record heat wave arrived.)

One basic suggestion that seems to cover yellowing of older leaves on a number of vegetables is to drench the root zone with seaweed or fish emulsion and foliar feed the top growth with seaweed (to increase the nitrogen content) I also already applied my "Dr. Earth" all natural fertilizer and my mineral rock dust in good amounts under the plants and watered it in--to assure that the proper amounts of the the minerals that the Cole crops need in the right amounts--calcium, boron, etc. are also present in the right amounts (in hopes of getting a dramatic turn around that way)? I am considering spraying everyting down with the seaweed foliar spray and perhaps adding fish emulsion to the soil at the base of each plant? Alot of the brassica family serious problems that all involve sudden yellowing of the lower leaves seem to involve application of "Parasitic nematodes"?? I don't know what those are or how to get them?

Fusarium Yellows seems to be the most dire "yellow leaf" problem and Rodale's says to destroy all plants if that is the issue and start over? As my plants are in the process of forming the first heads now (still) I am going to see what I can get out of it before taking such a drastic step! I will also try planting fall broccoli in another couple of weeks from seed--just in case this main crop crashes and burns?

If anyone has some helpful "tips" for me--this is only my second summer gardening and I am starting to use square foot gardening technique this year mainly with trellising my vining crops and tomatoes for the first time. Next year I plan more on using it everywhere....

Can someone more experienced please comment? Or make suggestions as to specific things i can do to stop these "yellows" (irregardless of cause) from advancing more? The rate this is happening is truely alarming...last summer this same thing happened but the growth of the broccoli plants themselves kept pace with it (the leaves yellowing and dropping happened at a much slower pace) and I got GREAT broccoli most of the summer despite the leaf loss--and the broccoli was great tasting etc. (just not the biggest heads). However, the DIFFERENCE between last year and this year is this yellowing of the older leaves followed by death of the yellow leaves is dramatically increasing in a matter of DAYS...I can see to where this could easily take the entire plant over in the next week to 10 days if I don't arrest it somehow? Please can some experienced gardener out there help me save my broccoli?

Thanks!!!

Distraught in Minnesota

P.S. The only reason I haven't gone "all out" yet with square foot gardening is I love to can, freeze and..as of last fall..dehydrate everything in as large quantities as possible to last all year and beyond. I have had to go to Farmer's Market in the past to buy enough for canning/freezing/drying of all the veggies. Using Mel's techniques over larger areas (but much of which are still "rows" of sorts within raised bed frames)--I have already doubled my yield from last year of most things..provided freak problems like this broccoli leaves turning yellow problem don't keep happening??

Hello Beth may I say welcome to the site.

You dressing the area around the plant with emulsion sounds good .
Are the stems of the plants sound and it's just the leaves ?


This plant has a slug chewed stem just below ground level


Was /are the pants solid in the MM or are they rocking back & forth in the wind?
How deep are the plants ?
This deep


or this shallow ?



If you can get pictures up on the thread it helps

Two more considerations to throw into the mix.

It's not uncommon for lower leaves to turn yellow.

You've had high temps way beyond the comfort zone of broccoli; I'm surprised they haven't bolted yet.

I have found that usually bottom leaves turn yellow and fall off. If the upper ones look fine then I would not worry at this point. I usually pull them anyway to avoid them drooping on the soil. And as I plant smaller plants like lettuce under them so I want the sun in anyway.

I just had to pull my broccoli this week. No heads due to the heat.

Agreed, I believe it is not anything you are doing but the environment is just not supporting this particular plant right now. It has been way, way to hot. You may want to plant some seed inside and transplant them out in the garden in a several weeks, perhaps you could have a fall harvest of brocolli!

When you pull up a plant that is dying, look at the roots. Do they look normal? If you can post a photo of your plants.

Everyone here..thanks so much for being SO SUPPORTIVE!!! My goodness you are a great group of people!!! I am so GLAD I found this web community!!! I go through a "syndrome" my loving husband has coined as "baby gardener's shock syndrome" LOL every time any of the veggies I am working SO HARD to grow "goes south" and develops a problem. In fact ANY PROBLEM with any vegetable outside tends to send me into "panic mode" and I "run around like a chicken with my head cut-off" seeking "THE ANSWER" trying 1001 ways to solve whatever is going wrong outside--sometimes burning inordinate amounts of money and TIME and personal energy until somehow I can turn whatever the problem is around somehow. I DO NOT take "failure" in the garden very well (despite being a "rank newbie") and I need to get to the point where I can personally deal with these problems a bit better and actually "ENJOY" my garden more instead of having it become a constant source of stress LOL....

That being said, I will go out this evening and take photos of the entire garden to give you all an idea of what I am doing (i know to "lay people"---like people in our neighborhood and friends and family who see our "backyard veggie garden wonderland".. Other people who see our backyard gardening paradise think we are "certifiably crazy" growing--and trying to grow--everything that we DO here in the "burbs" of Saint Paul, MN!! I need some "real gardeners" (the people who understand my PASSION) to perhaps tell me I am doing "ok" for a "newbie" at what all I am trying to do and some reassurance from you all would do wonders!!

I will also take some "detailed" pics of the broccoli for you--just understand that thus far, I have been pulling off the yellowed leaves (they are unsightly and DO upset me--so as we are trying to bolster the crop, I pull the yellowed leaves off the stems (I know they will die and turn brown anyways and I DO have beets and green scallions growing underneath them so it helps the beets and scallions if I keep those inordinately large leaves off of them). Then, I compost the leaves (out of sight, out of mind?) So the pics I post here won't necessarily show the yellowing that is going down at this point but you can see the overall condition of the plants themselves (stem size, depth planted, spacing together--I will warn you they are spaced about 18 inches apart in a "swathe" of two rows that are "staggered"--which is CLOSE spacing for full grown broccoli and they DO look "crowded" unfortunately--which is partially the reason I am suspecting nutrition--or LACK THEREOF--as being part of the problem in addition to the adverse weather. But this would not be crowded by SFG standards. However, I DO know that if I had them growing in "Mel's Mix" things would likely be better.

To the lady who suggested I try for a "fall broccoli crop"--my problem is space. I have one 20 feet by four foot raised bed that is "empty" left (I have 14 raised beds for veggie growing altogether). I am a bit ashamed to admit that I also am just now seeding in my squash/cantaloupe/pumpkins and was going to "dedicate" that bed to "just squash" and bush pickling cucumbers (for pickle making). Maybe I should re-think that plan though and use the "last raised bed premium real estate" space for a fall planting of broccoli, cauliflower, and cabbage...peas off to the side...and things like spinach, chard, and lettuces? and forget the "dedicated squash-cuc bed"..or try to "fit the squash in" by stripping off grass in the open areas of my yard between where my dwarf fruit trees are located and amending the soil in those grass-stripped areas and just plant some squash hills out in the open and let them "run around" the yard instead of trying to "pen them up" in one raised bed with trellising on both sides of the bed? What would you all do? NOTE: once you see my garden pictures you may be better able to advise me in this area?

I know that with squash and pumpkins taking an average of 80 days to 100 days to develop and it now being almost mid-July, it is REALLY LATE to be starting from seed with winter squash--but I love all the various winter squashes so much and want to try--and we have no problems getting out massive frost hardy covers (protective to 22 degrees) in the fall and placing those on and off all the beds if necessary--last year we kept everything going up to Halloween and actually were finishing up canning our own tomatoes just before Thanksgiving--which is really awesome for Minnesota!!! So I am willing to commit NOW to covering the squash if necessary all the way to November if required--although given it IS a pain.... What does everyone else out there do to "make room" for growing these space hogs known as squash and pumpkins? (I digress..or rather have gone off on yet another tangent--but the broccoli is still #1 and of paramount concern right now?) Thanks for ALL your input...pictures will be forthcoming!!!

Snip the leaves off with scissors instead of puling of leaves ..there will be less damage to the plant and less chance of tearing it out .

Perhaps really soak each plant with several pints of water per plant over an hour or so then use a trowel to lift the plant and replant it deeper down so the roots don't get so hot and dry in future ..... water it back in well with another couple of pints per plant .
Maybe only do this with just a few plants so you can see if it works for you & your garden .

I have found that in my own beds I'm better off planting about an inch deeper tha I would normally have done ... this also appliesd to direct sown plants in quite a few cases so I've been lifiting all my brassicas and putting them back in ton just below the see leaf when they get four leaves.