In 2022, as part of the Weston Nurseries Sustainability Program, we began production of a line of native plant species for sale in our stores; we branded it “Weston Rewilding.” The Weston Rewilding line is made up of over 125 plant species which are grown from seed, including some species which are started by our production nursery team located in Hopkinton. You can find these plants for sale in our retail stores in the dedicated native plants display areas.
In order to grow plants from seeds in a production nursery, it’s a multi-step process which we’ll describe below, but first some background information…
In nature, the seeds of many native plants need to experience the cold and wet conditions brought on by Winter for several months before they will germinate. This internal programming prevents the seeds from germinating and growing into small plants shortly before the onset of Winter, as these small plants can be fragile and susceptible to the chill.
Seeds, however, are very tough and the plant embryo inside the seed can find shelter there until warmer conditions arrive in Spring. Once the seed feels the warmth and sunlight, they spring into action and germinate in optimal conditions for growth and survival! This survival technique has been employed by plants for millions of years, so it is time-tested and effective.
Seeds that don’t experience the Winter conditions may germinate in time, but often inconsistently and inefficiently. At least from the perspective of a production nursery!
In an attempt to mimic Winter conditions and achieve consistent and timely germination in a production nursery, growers perform a process called seed stratification in a controlled environment (usually some sort of refrigerator or cold room). Different species require varying lengths of time (from 30 to more than 120 days) to properly stratify, but we usually start stratification of all the species we grow from seed in December (as more time than required by the species is not critical, whereas not enough time is critical).
To prepare seeds for stratification, they must first be collected responsibly, dried, removed from any outer coatings (this process is called threshing), cleaned and separated from extraneous plant tissue (either through the use of different size sieves or by using blown air (this process is called winnowing)), and finally the seeds must be counted or weighed in order to ensure we have enough seed to produce the number of finished plants we want to grow for our customers the following Spring/Summer. Once we have the number of seeds we need, the seeds are spread out on to moist coffee filters, placed in plastic baggies, labeled, and popped into the fridge for their Winter nap.
If you are interested in following the next step of our native seed propagation process, we’ll begin the seed germination phase in late February/early March in one of our retail greenhouses in Hopkinton which will have customer viewing areas! Stay tuned for future updates in our weekly newsletter.