I'm a newbie wintersowing, but I love growing broccoli. I can't say that that my answer is exactly right though because every broccoli year has been different. Based on my experience, broccoli bolts because of stress, not necessarily temperature (Though that can cause stress.) Any rapid change in temperature (Like say, 20 to 30 degrees' change in a night) drought, and even bugs, appear to have caused my broccoli to form heads. You should be okay if you keep your broccoli well watered and well mulched to avoid those problems. But like I said, that's just my experience. Maybe someone else can better explain.

I just ran into this thread. We've been patiently waiting for our dozen lush broccoli plants to produce heads but I'm now wondering what we did wrong. Planted seeds the first week of April. Plants are huge with lots of leaves. We check plants several times a day - I've picked off several tiny worms from the centers of the main stalks (where I expected heads to grow any day now). This is an old raised bed; we bought the house last fall from an organic gardener who composted. Had lots of sun, lots of rain, temps in upper 80's.

You planted it *outside* 6 weeks before last frost? As seeds or plants? Either way, in my opinion, leads to sloooow growth. Many 'spring plants' do much better in the fall (in my zone). Take a look at days to maturity from seed and work backwards from your average first frost date. Also, with a new bed, particularly one made from Mel's mix that has no nutrient value whatsoever beside the compost will take a good year of supporting plant life before it becomes fertile enough to get good, rapid growth of spinach or lettuce without some supplemental fertilization. Fish emulsion would be a terrific fertilizer for a new SqFt bed. It isn't that compost isn't great, but my experience particularly with store bought compost is that it is like cheap whisky compared to a fine, aged liquor. It can become garden gold, but initially I think it is just quick composted, bagged up and left to sit outside in full, hot sun on pallets until someone buys it. Give it a few months after supporting plant life and give the biology of the new bed some time and things will only improve. I suggest putting in a fall crop and supplement every couple weeks or so with some diluted fish emulsion and I bet those beds grow you some really tasty spinach and lettuce.

Bon, They might be fine. With onions you just never know. My onions have no mulch on them this year and I don't intend to mulch until and if this infernal rain stops falling. I need for the soil to be able to dry up as much as possible in between rainstorms or in between rainy days. My usual heavy mulch strategy is on hold for some areas of the garden because the soil is far too wet as it is and I don't want for mulch to prevent it from achieving whatever little bit of drying out it can get between storms. I think one reason I have so many lovely volunteer plants this year is because the onion bed is not mulched. From that bed, I have dug up and moved hundreds of Laura Bush petunia seedlings, hundreds of moss rose seedlings, and dozens of catnip, basil, lemon basil, and chamomile seedlings. That onion bed is the gift that just keeps giving, and I didn't even use all the seedlings I dug up. A lot of them got pulled up and composted. It is relatively weed free and volunteer free now, but I weed it every single day that rain doesn't keep me out of the garden like it is doing today. I see good onion plant great, nice leaf development and happy plants, but even well-amended clay in raised beds can stay too wet if the rain falls several days a week like it has been falling lately. I'd have it mulched if I could, but that would almost guarantee the onions will rot. So, you know, even though you're drier than we are, the lack of mulch might not be hurting the onions as long as you keep them well-weeded. More so than most plants, onions cannot abide competition, so keeping them weed-free helps produce bigger, healthier onions. I have the pathways mulched to prevent soil splash and its related diseases. I have the tomato beds, the rows of sweet corn and the bean beds mulched to prevent soil splash and related diseases. I have the flowers mulched. The onions, though? If they are to survive, they must remain unmulched. Including the rain that has fallen on my garden today, we're approaching year-to-date rainfall of 14". It sounds good, no? Well, actually, no. That much rainfall this early hurts as much as or more than it helps. I'm not panicking yet, but after looking at my forecast for the next week, I am starting to think the back garden will not get planted because it is going to stay too muddy too late in the season. More and more this year's rainfall reminds me of 2007---when I still had tomato and pepper plants in containers in May and June because I couldn't put them in the ground.....and the plants in the ground were waterlogged and growth was stalled and some were dying. I ended up planting a lot in cat litter buckets and 5 gallon buckets that year because there was no other way to do it. Peppers are perfectly happy in cat litter buckets, but indeterminate tomato plants in 5 to 7 gallon pots require an incredible amount of water and fertilizer to stay happy even when the ground is too wet for them. 2007 was a horrible weather year. While 2014 started out kind of wonderful, the longer the rain falls, the more likely we see a repeat of 2007, or even 2004. While 2004 was great overall, the spring was far too wet with over a foot of rain in one month. I want rain and I appreciate getting it, but we're at the point that it is too much at once. I don't even remember what my onions did in 2004 or 2007 but I think they struggled and some bolted and some died. I always plant tons of them to allow for some to drown, burn up in drought, or be pounded into oblivion and our crazy weather is why I do that. I wish we could send all this excess moisture over to SW OK, particularly to the Altus and Duncan areas. Their lakes would love all the water runoff we are having here.