Challenges of seed saving in a small garden
This is wintercress, a great peppery winter green around here. I had plenty available all winter. I only grow one type - from plants a friend gave me last year, and billions of plants are now blooming all over my garden (it self-seeds readily). The mature plant doesn't take up much room, so I'll be letting a few put out seed pods and collect their seeds.
I always hate ripping up my kale, but they had gone to flower and I wanted to plant the bed with another crop – part of my intricate management plan for my urban lot ecosystem. We made one last harvest* then pulled up the plants and tossed them in with the chickens. Some sprouting broccoli buds were still poking out of their foliage, but aphids had moved in. The little bugs stay put even when soaked and once I know they are there, I don’t want to eat them – so we harvested the leaves instead. Broccoli leaves have the same brassica flavour as kale, but aren’t as tender.
Both the kale and broccoli represent a good portion of my winter garden produce and, over the last few weeks as I watched them put up their cheery yellow flowers, I couldn’t help but ponder if I could let them go just a little bit longer and harvest their seeds – a further step towards sustainability.
I went to a seed saving workshop at the library last week (our library also hosts a seed library, apparently the first seed library in Canada, how awesome is that!). I’m now set to save some of my seeds this year – most everything I grow is open pollinated which is clearly labelled on the seed packages. Open pollinated seeds mean that the seeds will grow a plant the same as its parent. This group includes what is referred to as heritage varieties. The alternative is hybrid plants, labeled as F1, where two distinct varieties are crossed to produce a version that contains the best attributes of the parents. The downside is, if you collect seeds from a hybrid plant you don’t know what attributes will show up in the next generation (it likely won’t be as good as the original hybrid plant).
At the talk, genetic diversity in seed saving was discussed – this is where my seed saving plans fall down a bit. Brassicas, like my kale and broccoli represent two challenges. First, they are pollinated by insects and readily cross-pollinate with each other (called outbreeding). To save seeds I would, for example only be able to grow one type of kale (currently I grow three or four with the thought that if one type doesn’t thrive, other types will) as the isolation distance for kale is over a kilometre – way bigger than my yard. An alternative, would to only let one type flower.
If I were diligent and only let one type of kale flower, I could leave a few of these plants to go to seed and save those seeds, for an example I'll pretend I'm only letting one plant go to seed. The problem with that is that over time, I would be removing the genetic diversity in the kale. Over time, my kale plants would loose resiliency to diseases and change, potentially dieing off could. I could let more than one plant go to seed – but here is where I get into a bind, my garden isn't big enough to let everything I'd like seeds from go to seed and plant food for the next harvest.
This year I’ll stick with the simpler self-pollinating plants such as tomatoes, peppers, and beans. Isolation distances aren’t as much of an issue, although I still might have trouble maintaining genetic diversity over time – the solution to that will be to continue trading seeds with friends.
*ironically my husband ordered me the kale book I reviewed a while ago as a surprise, it arrived the day after we ripped out the kale.