Want to Plant Those Fruit Tree Seeds? Let’s Talk About Genetics First.
The fruit was delicious. That apple, peach, or pear — amazing. If only they could all be so good, and better yet, available in the backyard…
We’ve all been there. As a kid, there was not a seed left unsprouted, most transferred among the petunias in my grandmother’s Chicago apartment flower bed, or if I got lucky I could haggle a used blacktop bucket from my grandfather to grow my orchard between the apartment buildings.
Why did I never get fruit?
Because directing plant sex is a messy business.
Tree fruit breeders carefully observe potential parent plants for desirable traits. Fruit quality matters, but disease resistance, shipping quality, size, and other factors are crucial to a good commercial fruit tree. With these traits in mind, breeders orchestrate careful crosses based on those years of observations and/or deep genetic analysis. They then plant hundreds to thousands of offspring, committing to years of labor, fertilizer, water, chemistry, fuel, space, blood, sweat and tears.
That expensive and time consuming effort might bring one new fruit tree that approaches commercial quality.
So while it is fun to plant the bonus seeds that you get for free with the purchase of a fruit, here are some reasons why you might think twice before dreaming of your own fruit tree that captures the magic of that spectacular original fruit.
1. Too Young for Sex. Tree crops have juvenility periods when they can’t reproduce. It may take a seedling many years before it is competent to flower. You might have to wait 4–15 years just to find out the fruit are horrible.
2. Losing the Genetic Lottery. Commercial varieties are selected for disease resistance, fruit quality, shipping, etc. That genetic deck shuffles upon pollination and the likelihood of a decent fruit is horribly low. There will be extensive variation for traits that affect yield, disease sensitivity and fruit quality (size, flavor, color, texture). It is likely that the tree will succumb to disease before it ever flowers.
3. One Lousy Parent- Many fruit trees are self-incompatible, meaning they can’t fertilize themselves. The fruit itself comes from the maternal tissue, meaning that the fruit flesh will be consistent regardless of who fertilizes the flower (+/-). But the pollen must come from somewhere else. That means the grower needs to plant a pollinizer, a tree who’s only job is to make lots of flowers and over a long period. Make good fruit, notsomuch. Those genetics then become half the genes in seeds found within commercial fruits.
4. Inbreeding Depression- In the case the tree did self fertilize you’ll typically observe a marked decreases in fitness in the subsequent generations. Think of it this way. With each generation of self-fertilization the seeds are 25% less diverse at the level of the gene. With that uniformity comes the fixing of deleterious traits, like sensitivity to disease or pests. Mutts live a long time and purebreds get strange diseases. Narrowing the genetics can have consequences.
5. Rootstocks. Fruit trees perform best when they are grafted to elite rootstocks that match your growing conditions. The genetic marriage matters- the top part makes superior fruits, the bottom part makes superior roots. Your sprouted seeds, on their own roots, may limp along in strange soils, replete with microscopic pests that challenge its growth.
All of that said, it is super cool to play with seeds from a purchased fruit. I do it all the time because I thrive on failure and disappointment. I always feel bad when some enthusiastic plant fanatic asks me why their seedling died, why it has been 7 years and ne’re a flower, or why their peach tasted like popcorn shrimp. It’s complicated biology in that little embryonic plant, and with a few exceptions (e.g. some citrus) fruit trees are genetically a mess and usually don’t produce offspring that approach the quality of the parent.
Sorry for the wet blanket. If you want to invest your time into growing productive fruit trees, grafting is strangely satisfying and you get results fast. It’s a neat skill, a fun thing to talk about at parties if you hang with nerds, and you learn a lot about plant biology too.
And the internet makes finding scions (the part you graft) and rootstocks (the part you graft to) easy. There are tons of fun varieties online from professional nurseries and hobbyists. Why reinvent the wheel? Here are a few of my favorite places to find neat materials:
https://fruitwoodnursery.com/
https://www.copenhavenfarms.com/
There is something sacred about pushing a seed into moist soil and witnessing the emergence of a new plant. But don’t let that heartwarming joy override the stark, cold realities of genetics. Growing your own food, or food for others, is a noble venture. That’s why we have to accept the limitations of biological reality when enjoying growing food crops.
Dr. Kevin Folta is a Professor of molecular biology and genomics of fruit crops at the University of Florida. His family grows vegetables and fruit crops for farmers markets. The opinions expressed do not necessarily represent those of his employer, and no endorsement or association is implied.
