However one thing confounded us. At first the tomatoes we planted in the front garden grew just as happily and just as fast as the ones out the back, all of them delighting in the summer sunshine, but then EPIC FAIL! The ones out the front got one then two then a veritable patchwork of horrible yellowy brown spots! They shrivelled away. We ran to books and blogs to work out why. Apparently before we moved in, this north facing position had been prime tomato territory and this was our first introduction into the need for crop rotation.
Just as you would become malnourished if you ate nothing but tomatoes and potatoes, growing things from the same family year after year in the same spot will create an imbalance in your soil. Plants from the same family such as Solanaceae (that’s your tomatoes, potatoes, eggplants, capsicums and chilis) have similar nutrient requirements so they will strip every last bit of these from the ground. But more importantly rotating your crops reduces the spread of soil-borne diseases and pest problems as these guys attract the same nasties.
So here are the four main groups we suggested for the Coburg Blitz:
Plot A: Umbeliferae (carrots, celery, parsnip, coriander, etc) followed by a green manure in the cooler months to replenish the soil for the next year’s crop
Plot B: Solanaceae (tomatoes, eggplants, capsicums, potatoes, etc) which are very nutrient hungry with Alliums (onions, garlic, leeks, etc) in the cooler months
Plot C: Legumes (peas, beans, etc) that fix nitrogen in the soil ready for a nutrient hungry crop to follow
Plot D: Brassicas (broccoli, cauliflower, cabbages, brussels sprouts, etc) that need a nutrient rich soil
And the next year the nutrient restoring crops will be replaced by the nutrient depleting crops. The root crops following the nutrient depleting crops, as too many nutrients in the soil result in very bush leaves, but disappointing roots.
The beauty of this system is that plants not in these main families such as many herbs, flowers, lettuces, beetroot, silverbeet and spinach can be mixed in amongst each plot to allow all plants to benefit from companion planting. For a full list of the plant family groups I recommend checking out The Seed Savers Handbook. This system is really ideal for a sharehouse, where each housemate can look after a bed themselves and not have to work about other people growing things that will cross-pollinate with their produce come seed saving time. I’m excited about suggesting this to my housemates … but first 1 Permablitz down 2 more to go until we can do our own garden!!
Click on the images above to view larger on my flickr.
Please comment on this post if you found it helpful, I’d love to hear about your gardening adventures!
19 Comments
Thanks so much! Crop rotation always confused me!
Looking forward to more guides!
Sally
This is great, thanks. Just wish I could see the fine print on the last few pics.
Thanks so much for commenting, it’s lovely to know that it is helpful. You can click on the images to view them larger on my flickr account.
The list of plant families can also be found in the Seed Savers Handbook and I really recommend it to people who are looking to grow vegetables, it is an amazing resource telling you the origins of the different veggies and how to cultivate and save the seed from them. It also tells you how to avoid cross pollination between different veg which is really fascinating.
http://www.seedsavers.net/seed-savers-handbook-more-info
In the midst of my permaculture studies I am so ecstatic to discover this dreamy diary of your garden antics, especially the description of crop rotation. You have made such a beautiful blog, both in content and style.
Would you suggest a green manure crop before planting brassicas in a bed that was previously planted with umbeliferae?
Thank you for your lovely comment, it has been a bright spark in an otherwise dreary wintry day.
A nice nitrogen fixing green manure is a great thing to add before a brassica crop as they require a lot of nutrients to produce lush and prolific leaves. Something like clover or legumes would be perfect. 🙂
Wow, what a beautiful cyber segue I’ve enjoyed on a windy Saturday night in august.
And the fact that it’s one of those wonderfully serendipitous moments that life, gardens and the life of a gardener throw our way makes it even more wonderful.
I’m a garden designer, horticulturalist and teacher. I work with Swinburne teaching across a few subjects in the Sustainable Landscape Design Diploma and with SGA presenting workshops on all manner of sustainable garden topics, including companion planting, crop rotation, organic soil care and so on. Which brought me here, to the serendipitous moment.
In a class today I was talking to a few students about CAD (something I teach, but not today’s class) and how CAD plans can often look flat and lifeless. The rendering too often looks sterile. I went on about Edna Walling’s designs and how her plans were artworks in themselves. And here I am looking at your beautiful work. They’re illustrations that sing about the beauty of plants, gardens and harvest. And they do such great credit to permaculture and the design of beautiful permaculture gardens, which sometimes, perhaps too often, sacrifice aesthetic beauty for functional need. Our gardens are after all places that deserve to be given the opportunity to glow. I’ll be pointing my students to your site to see the beauty of your plans and illustrations.
But the reason I found myself here tonight was because I was looking for some inspiration, some new ways to tell a familiar story about crop rotation and plant nutrient cycles. I’m speaking to a group of gardeners in the Yarra Valley tomorrow about summer veg and berries and the use of crop rotation. Your drawings have really distilled a topic that troubles some people into a beautifully simple piece in the tapestry of seasonal gardening. Da Vinci like. I’ll also be pointing this group towards your site as an example of how they can ‘make it work’.
Finally, I’ve been on the Permablitz mailing list for too long. I’m always tied up doing something that keeps me from the next blitz. Before the end of the year I’ll be there.
Thanks guys for sharing your magic with us.
Wow Michael! What a beautiful comment to come home to! It’s lovely people like yourself that make blogging worthwhile.
I am very touched by your kind words! (Edna Walling is a huge inspiration for me)
I hope you do come along to a Permablitz soon, its a great way to meet like minded people! Perhaps we’ll see you at one!
Thanks for your diagrams and lovely illustrations explaining crop rotation. I was wondering where celery fitted into the picture and now I know.
Loved the watercolor diagrams! Beautiful work. I wonder if the brassicas and the solanaceae family could be interchanged? Seems like the legumes providing all that nitrogen for the season, versus a shorter nitrogen cover crop, would do more good for the leafy bits; and then the solanaceae can have the shorter nitrogen fixing green manure ahead of them. Thoughts? Thanks in advance! Very inspiring!
Hi Mitchell, thanks for your comment. You are right that the brassicas and solanaceae could be swapped, both rotations have their pros and it’s just about working out what works best for you. 🙂 I like the overlap I get in terms of companion planting with the alliums and the carrots and the freedom to use a mustard in the green manure before the other brassicas go in, but I’m sure there are other beneficial transitions you could make use of with a swap.
With the green manure, despite the shorter time it is in the ground you cut it back and dig it into the soil before it sets seeds. When green manure flowers/fruits/seeds it uses up nitrogen stores and when they are harvested you are taking some of that nitrogen away rather than putting it back in the soil. I believe there should be plenty of nitrogen put into the soil by say an autumn/winter manure that is slashed in spring (or a spring/summer slashed for autumn), and just as with tomatoes that have it too good, too much nitrogen will lead to lots of leaves but few heads forming on the broccoli and cauliflowers.
Thank you so much for this, it has really helped me with my assignment on crop rotation.
That’s so good to hear, glad it helped.