You can have great success with broccoli in northern climates. It’s a cool-weather crop that doesn’t mind cold nights or even moderate frosts, and grows best in daytime temperatures between 10C and 24C.
Broccolis and the other cabbage-related crops (“cole crops”) like their soil pH in the normal-to-slightly-alkaline range. Many soils in our region, including mine, fill the bill. However, if your soil is peaty or sits on a layer of rock, it may be on the acid side and not good for the cabbage family. Grow blueberries, beets or potatoes on this instead. If you know that your soil is somewhat acid but you’d like to try broccoli, you can give the pH some help by using bone meal and wood ash as fertilizers, along with possibly amending with a load of non-acid topsoil.
As I’ve mentioned elsewhere on this site, you can make a special contribution to biodiversity by growing your own broccoli. According to Michael Pollan in his recent book, In Defense of Food (a very good read, by the way), half of all the broccoli grown in the USA is one variety: Marathon. Nothing wrong with Marathon as a variety, but if you’ve been gardening for a while you know that different broccolis have different colours and subtly different flavours. Try many!
In 2008 I tried two early varieties, Windsor (56 days) and Belstar (66 days), both from Johnny’s Seeds. Intending them for the farmers’ market in late August, I planted in mid-June – but that was a mistake. Both varieties took longer than I expected to reach maturity, and picking did not start until late-September on Windsor, and mid-October on Belstar (after I was finished at the market).
The days-to-maturity quoted on seed packets can be tricky (this is my excuse). Some seed houses count the days after emergence, and others count the days after transplant (in species that are commonly transplanted). Whatever the case, in my experience it takes 10 weeks from emergence to maturity in early broccoli here in Thunder Bay region.
Aside from my timing problems, both varieties performed well. I think Windsor is the more attractive of the two, as it has the bluish colour that veggie consumers seem to look for. It also forms lots of side-shoots after the main harvest. My Belstar planting never had time to form side-shoots, but it’s reputed to provide lots of them. Side-shoots are always a boon whether you eat the broccoli yourself or sell it – bunched side-shoots are just as attractive as whole heads, and many customers actually like bunched broccoli better because they get lots of tender stems.
From 2009 to 2012 I planted Windsor. As I mentioned, it’s not early, but it’s reliable, doesn’t mind a hot summer, and makes nice blue-green uniform heads.
In 2013 I got transplants from a friend that turned out to be Green Sprouting Broccoli. This is a heritage open-pollinated variety, relatively early, very tasty, constantly productive. Downside is that the plants take a lot of room as they sprawl. As an open-pollinated variety, there is a bit of variability in the plants – slightly different colours and maturation dates. Some plants formed an early central head, and some just stayed with side-shoots. Quality was excellent, and if you like those tender, asparagus-like stalks, Green Sprouting Broccoli is for you! And, of course, if you are a seed saver, leave a few good-looking heads to go to seed (if you can bear to) and you’ll have seed for next year.
In 2013 I also tried out Gypsy, but it didn’t work all that well for me. It was barely earlier than Windsor, a slightly greener shade, and the heads tended to be a bit uneven as far as bead size. It was apt to burst suddenly into bloom (ta daa!). I think Windsor is more heat tolerant. We do get quite torrid summer weather here.
Wendy (author), Aug. 13, 2009
Me again – I just noticed a new article on Broccoli spacing and irrigation in the online Fruit & Vegetable Grower magazine, here: http://www.fruitandveggie.com/index.php?option=com_content&task=view&id=2427&Itemid=137
The researchers found that although they increased net yield with a spacing of only 20cm between plants (they used the variety Marathon, of course!), disease and unusable plants also increased.
They also tried double rows of staggered plants, but found weed control to be an issue.
Twenty centimeters is very tight for broccoli plants. In the home garden or small market garden, unless space is at a real premium I’d go for 26-30cm between plants. I crowded my plants in 2008, and every third or fourth plant was stunted and never formed a large head. Just my two cents.
Matthias, Aug. 21, 2009
Although this year has been too cool for good corn and melons, the cole crops have done quite well. Broccoli is a favorite of ours, and every year we seem to grow it a little better. I love the varieties Early Dividend and Gypsy from Veseys seeds. In theory these are early and mid season variety’s, however due to the super slow weather, they both matured only a week apart. We transplant our broccoli into beds, covered in biodegradable corn starch mulch. We stagger them on 14 inch spacing, 2 rows to the bed, 400 feet long. The Early dividend variety produces 2 good pickings of florettes. With the two varieties and picking florettes we kept the CSA in Broccoli for 3 weeks.
Glad to have a forum for nothern Veggie growing.
Keep up the good work,
Wendy (author), Aug. 21, 2009
Thanks for your input. Staggered plantings on a layer of mulch sounds like a great idea and eliminates any weed problem. I’ll keep an eye out for the varities Gypsy and Early Dividend and maybe make a comparison next year.
Whenever I use some of my garden space for something that doesn’t work, I think, “I wish I’d planted broccoli there!” It’s so popular and grows so well up here.