The power of landraces

VermontCathy Posts: 1,991 ✭✭✭✭✭
edited July 2022 in Vegetables

I recently purchased and read Joseph Lofthouse's book Landrace Gardening. I highly recommend it. It is a small book that is a quick read with interesting ideas that aren't much discussed elsewhere.

Lofthouse is not a fan of heirloom varieties, which he considers needlessly inbred and adapted to conditions 100 years ago rather than conditions today. Instead, he recommends that home gardeners grow landraces, which are genetically diverse groups of different varieties that are allowed to cross freely.

Your local conditions, including weather, insect pests, and other factors will make some of the varieties fail quickly. This is a good thing, not bad. Lofthouse plants as many varieties as possible and expects the vast majority to fail. The survivors become adapted to your local conditions and outperform better-known varieties.

Other writers and bloggers have written about landraces, usually inthe context of outbreeding plants such as spinach, cucurbits (cucumbers, squash, etc.), and broccoli. These outbreeding plants need a certain amount of genetic diversity, or they will quickly suffer inbreeding depression and in just a few generations fail to thrive.

Lofthouse encourages us to use landrace techniques on plants that are inbreeders, too. One of his biggest projects has been crossing wild tomato varieties with many types of domesticated tomato to produce a landrace that can easily cross-pollinate itself. The result has much large flowers with extended stigmas that pollinators can reach, a wider variety of flavors withsome reminescient of tropical fruits, and better ability to handle diesease and adapt to more locations.

I had never realized that tomato flowers normally self-pollinate before they even open. The stigma is sealed inside the anthers that contain the pollen, and by the time it opens the stigma is already self-pollinated. That's why it's so much work to cross tomatoes. But by breeding in wild tomato relatives, the huge flowers are wide open, contain large amounts of pollen, and are attractive to bumblebees.

Landrace gardening is something I definitely want to try in 2023!


  • Hassena
    Hassena Posts: 345 ✭✭✭

    Hey there, I am taking a seed class with the Organic Seed Alliance and LOVE IT!

    It's recommended to have about 80 plants of a variety a grower wishes to save. For diversity.

    Many beans are also self fertile. The bean flowers pollinate themselves the night before they open. WOW?! what??

    plants are amazing and saving their viable seed puts us in thriving homesteads.

    Thanks for sharing his book info. It's a great book

  • VermontCathy
    VermontCathy Posts: 1,991 ✭✭✭✭✭

    Many small gardeners don't have room for 80 plants of a single variety. However, if you share seed with others in your community, it's the total number of plants that matters, not the plants per garden. So if five gardeners grew about 15 - 20 plants each and all shared their seed, they should be able to maintain the variety.

    It also matters whether the plant is an inbreeder (tomato, lettuce, pea, beans) or an outbreeder (spinach, cabbage, corn). You can maintain a variety with a smaller number of plants if it is an inbreeder.

    Tomatoes are also usually self-fertile, pollinating themselves before opening. This is an adaption to regions that lack the pollinators that tomatoes (originally from South America) used to depend on. The anthers are actually completely closed around the stigma. Take a look!

    The Lofthouse tomato landraces have cross-bred in wild tomato relatives, restoring the natural outbreeding with larger, open flowers. Solitary bees, such as bumblebees, can do a good job of pollinating them.

  • Megan Venturella
    Megan Venturella Posts: 678 ✭✭✭✭

    I started reading that book as well! So so interesting and it made me less afraid to save my own seed- which alone was worth the purchase!

  • VermontCathy
    VermontCathy Posts: 1,991 ✭✭✭✭✭

    @Megan Venturella I have saved seed before, but I used to be very concerned about keeping different varieties separate. This book made me realize that if I have two or three good varieties of a vegetable, there is no reason I need to keep them from crossing. I can weed out bad combinations later and may be rewarded by some very good ones!