Landrace question

Greetings!

I’ve read the landrace seed book by Joseph lofthouse.

I have a question.

I live in zone 6b with a hot dry summer.

Do you create seperate seed banks for spring gardening and fall gardening?  I have selected a bunch of seeds to save that did awesome with no irrigation in a hot dry summer, but our climate will change completely for the fall.  Am I attempting to breed seeds that will do both or have two seperate seed banks?

In the pragmatic world in which I find myself, it's easier to only keep one landrace per species. By planting one landrace in both the spring, and in the fall, I am selecting for a population that can be reliable in either scenario. There might be a cost associated with that choice in that populations selected for only fall or spring might yield somewhat more. The simplification in record keeping and seed saving entices me to keep only one population per species.

There are a lot of environmental and gardener influences on a population that will be the same regardless of whether they are spring or fall planted. If I were keeping two populations, I would plant some seeds from each population with every planting, in order to maintain diversity, and to share adapted traits between populations.

Eric Hammond wrote:Greetings!
Do you create seperate seed banks for spring gardening and fall gardening?  I have selected a bunch of seeds to save that did awesome with no irrigation in a hot dry summer, but our climate will change completely for the fall.  Am I attempting to breed seeds that will do both or have two seperate seed banks?

I often plant different things at different times. For example, I'll soon be direct seeding carrots, onions, and various brassicas in spots where corn and beans are just about finished maturing. Yes, many will think it's a bit weird to direct seed those things in July or August, but it's been working well for me.

I've also been striving for several years to reduce maturity time as much as possible in all of my crops. When it comes to the same species for example with beans, corn and tomatoes, and in a climate similar to you yours, I've been working on growing two generations in one season. A couple days ago I direct planted small patches of all of those from mature seed that I harvested a few days before.

It's all the same seed though, I don't keep those planted in early May separated from those planted in late July. I do that mostly in an effort to develop varieties that can be planted pretty much anytime, thereby extending the window of opportunity to start over in the event an early planted crop is lost for some reason.  

I agree with all that has been said above, but I will add one thought for consideration...It depends on your specific goals.

For example, if I am growing two sweet corn crops in a year, and one of my goals is to develop a more cold/wet germination/seedling tolerance for earlier planting, then those conditions can only be selected for in the first planting of the year.  The conditions are simply too different in July with it's 100+ degree heat and differing sunlight/pest conditions.  

Ideally, as Joseph said above, you could still plant your one landrace of early/cold/wet germinating seed in July, then select for other traits like drought tolerance.  This would, over time, refine your mix to both extremes, making a pretty hardy corn.

In my case, I'm experimenting with a mixture of about 20 varieties of sweet corn, some hybrids and some OP for my second crop.  I had a real difficult time with mice digging up and eating my seed, which wasn't an issue at all for the early planting.  So, each time I replanted the "holes," I just kept planting different varieties with different DTM over the course of a few weeks.  I'm to the point now, where I have a nice stand of corn (albeit with some "holes" in my rows).  They are all different varieties, and the beginnings of my own sweetcorn landrace.  I know I have many more years worth of selective seed saving before I get the results I'm working toward, but it's fun nonetheless.  Now if I could only find more land to plant in corn, this project could grow exponentially...