For our zone the #1 answer IMO would be to plant hybrids. I've had good results with Bubbles and Jade Cross. For your area there might be other important considerations. .. E.g. Timing. Is important.

I took the first leaves off of the bottoms of my June-planted b sprouts yesterday. The little buds are just showing, so I'll take off 3-4 leaves a week for the next month and pinch out the tops in mid-October. I've been fertilizing as heavily as I would sweet corn, and still the sprouts won't be huge. The harvest period is usually mid-Oct through late November, with the last few weeks under row cover because of deer.

I have been learning about fertilizer, slowly, and I suspect that this is a crop I need to work harder at applying fertilizer.
So far it has been planted in my best sun, beds that have had compost, and rotted horse manure the year before, and an organic 4-10-4 application at set out. Like Planatus I set mine out in June. So, I am going to get a crop of fava beans in as early as I can next year, after compost and manure this fall. Also read up on top dressing.

This year I will try the leaf removal above to see how well that goes. Any thoughts on a foliar feeding now, September?

Here's a photo of one of my plants from last fall, around mid-november. The plants were just about up to my chest. This year they look to be similar with good growth and tiny spouts just forming.

I've never removed a leaf before it yellows, but do top 1/2 the plants to get larger sprouts for thanksgiving. I also don't add any nutrients other than a good composting before planting.

I think that everyone has said it already, good fertility, good varieties and proper timing for that variety. I prefer the longer maturing varieties (120 days), so that I can get the plants up and growing before the hot summer months starts. The variety in the photo is "Cumulus".
-Mark

How do you grow brussels sprouts in zone 6? I tried planting them in July and the seedlings are just now starting to grow, they couldnt take the heat. Growing them for a Spring harvest would probably require starting indoors very early. Any suggestions on what/when to plant? It sounds like I should transplant established seedlings in June? Hard to get much indoors not looking leggy and weak... Might as well just plant outdoors, it is good weather in Spring? I am going to try overwintering the seedlings I have but have little hopes for success.

Madronedeb: How hot does your summer weather get? And for how long? Night / day difference?

I usually plant out 6-8 week transplants in late May or early June, depending on weather... This year I planted Churchill F1, Johnny's, supposed to be 90 days. My garden has more shade than optimal, about 6-7 hours a day in best locations. So I usually look for shorter DTM and plan on 20% longer time to yield, so an October timeframe seemed reasonable for these plants. They are making sprouts, but MUCH smaller than yours. The cabbage planted in bed nearest Brussels are heading up nicely, and they were planted in July. Do they have significantly different soil fertility needs?

That being said, my other cole crops that we eat the flowers of: broccoli, and cauliflower, are doing splendidly, so I seem to have enough sun, and cool enough temps. Brocolli has almost gotten tiresome!!

We have only eaten 2 cauliflower, but I have minimal experience with whiteflowered crop so I am thrilled with any success. Picture following...

Summers here in western Oregon stay hot and dry from July into Sept. Temps usually stay in the 80's with jumps into the 90's every few weeks. This year we didn't get triple digits.
Nighttime temp are much cooler than in most places east, usually dropping to the 60's with occasional hot spells.

My sprouts seed the first week of May, transplant a month later. I'd think if you have good cabbage then your soil is fine for sprouts.
I hope they size up more.

-Mark

If you put your compost and manure on in the fall you are probably losing a great deal of nitrogen. Try putting chopped leaves and cover crops on the garden in the fall. If you chose the right crop it will use the nitrogen and can then be chopped in spring to give the nutrients back to the soil. Add the manure and compost in the spring.

I finally had success with brussels sprouts in my garden this year after years of trying and failing. I have a lot of compost in my soil and horse manure plus I also fertilized with dynamite all-purpose fertilizer granule. I have my plants covered with insect netting on the hoop house so the cabbage worms can't destroy them. I fertilized them once in the beginning of spring. I planted my seedling transplants the first week of April.
I found a YouTube video that was a lot of help from ThefarmwoodburyCT

It sounds like I should try planting, direct sow, an early variety in March, and a late variety in May (for Fall harvest), and see what happens... how's that plan sound? I already have too much going on indoors to start them indoors I think. (Zone 6b)

This post was edited by Peter1142 on Sun, Sep 14, 14 at 19:09

The first year I tried them, they grew beautifully! I think I planted them in June or July.
In those days, I didn't wear my glasses when I went out to the garden. When they were ready to harvest, I had my glasses ON and discovered they were INFESTED with aphids! Not the spray them off type, but the get rid of them type! LOL I haven't gone into the garden w/o my glasses since!
Also, the produce manager of the chi chi market I used to work at with sp Ed students said he doesn't even try for the organic BS in this area cause they are so damaged by aphids!
It's probably cause our growing season is so long and so is our aphid season! Nancy

Qbush:

I have gorwn sprouts many times in SE WI. I transplant the
seedlings into the garden in May. They are very slow to
take off. I fertilize heavily and still they grow little.

I find they usually do much of nothing until August then they really start pushing the growth. I like to slowly trim off
the bottom leaves a few at a time each week. I do feel this
forces them to grow taller.

Once Sept 15-20th comes, I cut off the terminal bud of the plant. This stops any new growth for height and really makes those baby sprouts grow big in size.

They are best left til November to pick as a few frosts really sweeten them up. Some around here leave them in the ground and pick for their thanksgiving dinner if we have a
warm enough fall.

Any issues on bugs are best controlled with Bt. I spray weekly to control moth and looper as needed.

I've mentioned it before but the tops of the plants which you pinch out make delicious eating. Pinching the tops out for the sake of the plants doesn't seem to be a thing over here. But we do cut off the tops purely to use as a vegetable.

Here is a link that might be useful: Sprout tops

Peter, don't try planting Brussels sprouts in spring. The plants will develop blasted sprouts in the heat of summer, very frustrating. WV extension recommends June 5 as a seeding date statewide, and I think they are on target. You could go a week or two earlier, but not later. The harvest period is mid-Oct to Thanksgiving. After that, repeated hard freezes take their toll, though I've had plants come through winter and bloom like crazy in spring.

I tried planting them in early July, and the seedlings just sat there, unhappy with the heat and not growing until the weather cooled, and I won't even be close to being on target to get sprouts this year unless we have a very mild December and I get lucky with Christmastime sprouts. I assume I will have similar troubles planting in June, it will probably be hot by the 4th of July. Was it perhaps the variety, can you recommend one for our zone for growing over summer?

TracyDR: That makes sense. My available horse manure does break down quickly, and in MA we have chopped leaves! I JUST happen to have bed very much like your description. I was planning onions, but perhaps I will put a few Brussels at one end, to test my soil!

Mark: I am rolling in cabbage immediately next to the Brussels, and they are just starting to head up nicely. Which is good, cause we just started eating second planting of Caraflex from another bed. I parked them there, on a lasagna compost system, sans carpet, from last year. I didn't expect much, soil was very young, but they are great.
Our summer was cooler than usual, nights in low 60's, and hi 50's. Most days 70-80, with a week or so higher in August. Basically perfect broccoli weather. A local vegetable gardening friend told me to look at calcium in the soil. Does low calcium affect Brussels, but not cabbage, broccoli, or cauliflower? My memory says it is a trace nutrient... Off to check.
KateQ