Why Are People Using Persimmon Seeds To Predict The Weather & Does It Really Work?

From inspecting the productivity of fruit trees and measuring the stripes on colorful caterpillars, to looking for moon rings and counting foggy August days, old wives' tales have often used elements from nature to predict the weather and prepare for harsher winter seasons. One especially popular American folk tradition involves using persimmon seeds to predict the intensity of winter. There is no scientific reason why farmers used this method for weather prediction, but it's a fun way to connect with nature and preserve local heritage.

This method has been passed down for decades. By collecting and cutting local persimmon tree seeds, gardeners can reveal the shape of the cotyledon inside to make some predictions about the upcoming winter season. Some gardeners would even use up to 10 seeds to predict the ratio of snow, rain, wind, and mild winter days. The truth is that, even though there's no science that ties persimmon seeds to the weather, the Jefferson County Extension office in Missouri has tested this method for 17 years and found that it can provide an accurate prediction more than 75% of the time.

To take part in this tradition, you first need to collect the seeds of locally grown persimmons, those that grow on American persimmon trees (Diospyros virginiana). These classic fruit trees can be found growing wild in USDA Hardiness Zones 4 to 9. Be aware that store-bought fruits of unknown origin won't provide an accurate prediction for your region, according to the folklore behind this tradition. You can also use fruits from your own persimmon trees or source some fruits from your neighbors or local nurseries. 

Collect the fruits in the fall or early winter when they have ripened. A good indication that the fruits are ready to pick is that they have a bright orange color and soft, almost mushy, insides. Once you have up to 10 seeds, clean them well and then leave them to dry. When your seeds are ready, cut the seeds lengthwise with a sharp knife to reveal the shape of the cotyledon inside. 

The cotyledon can be one of three shapes: a spoon, a fork, or a knife. The spoon shape indicates that you'll have a lot of snow to shovel, while the knife indicates that you'll have a harsh winter with strong winds that cut like blades. If the shape of the cotyledon is a fork, you'll have a mild winter with very little snow.

Because some garden plants can't tolerate cold winters or even brief snow periods, winter preparation is crucial, even if your persimmon seeds predict a milder winter. Thankfully, there are many ways to prepare your garden for winter. If you have a vegetable garden that has tomatoes, beans, corn, cucumbers, pumpkins, or any other non-frost-hardy vegetables, you need to harvest and store these before the first frost. Discard all diseased plants. Don't throw any diseased vegetables or leaves in your compost pile, as some fungi and bacteria can survive low temperatures and then spread to new plants. 

If seeds reveal multiple spoons, you might want to prepare your semi-hardy vegetables and herbs too, by installing cold frames or floating row covers. You can leave your root vegetables in the garden during harsher weather, but try to remove and store them before the soil freezes entirely. You can also add compost to the soil in late fall to give your plants sufficient nutrients over the course of the winter season.

If your prediction includes multiple knives, you can prepare your perennials by watering them well before the first frost. Because strong winds can cause water loss, watering before frost will protect the plants and reduce winter stress. Additionally, covering your garden beds with black plastic or cardboard can protect them from weeds and random seed sprouts.