Oh, just wondering what big quantities of food I could be eating in the autumn from a perennial garden. Jerusalem artichokes yes. Purple potatoes that never seem to be all harvested (counts as a perennial for me!) Braising greens that re-seed themsleves. Winter squashes that come out of the compost (I'd also count that in as perennial, or at least low-maintenance). Lots of fruits.
What else? My tummy is looking for something vegetably. Would I just get that fix by going for the abundant veggies like zucchinis? Not quite a perennial.
I have had the same experience with the purple potatoes! kohlrabi would probably reseed itself if you allow some to and could be in a perrenial bed. My peas also reseed, i always thin a few volunteers in the spring. walking onions. My peppers have really kicked into gear since it has cooled off and i always get some volunteers from them also. not that those are all really perrenials but if they are there the next year they can go in a perrenial be imo.
You can deliberately let annual and biennial plants go to seed so they can sow themselves.
But you do have to use open-pollinated (OP) types of veggies, not hybrids. Most hybrids will revert to one of the parent types, which are mostly inferior. They're a waste of soil space and water.
And some types are better to let go to seed than others, mainly the ones that don't cross-pollinate too easily. I wouldn't bother saving seed from any squashes if I was growing several varieties, or if I even grew one kind of squash and some gourds. I let that happen once... yuck! Apparently my summer squash (zucchini) crossed with my pumpkins (winter squash) and when I planted the resulting seeds the next year, I got these really weird-looking sort of roundish green things that tasted like weeds.
But if you have similar types of plants (family) that bloom at totally different times, you can use them, or save the seed from them. Corn is one you can do like this. If you plant three varieties of corn (early, mid-season & late), plant the early type first, let 10 days pass, plant the mid-season ones, let another 10 days pass, and then plant the late-season one. Due to timing, each type will "bloom" at separate times so they don't cross. I've done this with sweet corn and ornamental corn, planted in blocks right next to each other, with no problem in crossing.
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