Growing Pacific Northwest Shrubs from Seeds
The Pacific Northwest has a surprising variety of native edible berries. Some like salmonberries and thimbleberries ripen earlier in the season while others like snowberries ripen a bit later, but a lot of our native berries ripen fruit in the late summer. If you live in a different temperate area and have berries maturing in late summer to early autumn, it’s likely you can propagate them in a similar way.
Many of these plants can also be propagated by cuttings. Cuttings can be faster, but they are genetically identical to the plants the cuttings were taken from. They are a great way to duplicate a plant, but seed propagation leads to greater genetic diversity.
When fruit or berries ripen at the end of the season, they are full of seeds that want to become plants. But they don’t want to become plants until the conditions are suitable for growth. To ensure that they don’t germinate too early, the seeds require cold stratification to break dormancy. After the cold months have passed, the warmth of spring will awaken the seedlings or at least get them on the way (some can take a couple of years to germinate).
If you live in a warm area or buy stored seeds in the spring, you will want to artificially cold stratify those seeds before planting. You can cold stratify seeds in the fridge for several months, though some seeds are more reliable if they are cold stratified outside where the freeze-thaw cycle can help break the seed’s dormancy better than the steady temperature in a fridge.
Late Summer Pacific Northwest Berries
These are the type of seeds I collected last week (the first week of September). The top two from left to right are salal (Gaulthoria shallon) and evergreen huckleberries (Vaccinium ovatum). The second row is low Oregon grape (Mahonia nervosa) and red huckleberries (Vaccinium parvifolium). The last two are cascara (Rhamnus purshiana / Frangula purshiana) berries. It’s not a shrub, but this tree’s berries ripen at the same time.
I also started tall Oregon grape (the seeds were collected a couple of weeks earlier, so I’d already cleaned and dried them), and the previous day I started red-flowering currant (Ribes sanguineum). The tall Oregon grape (Mahonia aquifolium) berries look very similar to the low-growing species. The red flowering currant has beautiful flowers but makes surprisingly small seeds. The berries are dark blue and full of tiny seeds (much smaller than the comparatively large seeds of domestic currants).
Most of our Pacific Northwest natives have fairly small seeds. This squished open salal berry shows the light-colored seeds hiding inside. Salal berries aren’t particularly moist, and as long as some critter doesn’t run off with them, you can also find some starting to dry, in which case they are a little leathery packet brimmed full of seeds.
This is a similar, smaller berry. If you squish open the berry of evergreen huckleberry, you’ll find a pile of tiny seeds (the orange-tinged bits) hiding inside.
If you have a lot of berries to clean, you can smash them in a bowl with a fork or run the berries through a food processor. After you smash up your berries, you can fill the bowl with water and scoop out the skins (most of the seeds will sink to the bottom of the bowl).
Red huckleberries have smaller, and a bit drier berries, but they can be cleaned in the same way. Here you can see the tiny orange seeds.
Oregon grape seeds are much larger. If you just squeeze the berry, the seeds will pop out. They only have a few seeds per berry, but they are easy to find.
And even though the cascara is a tree, its berries look like large evergreen huckleberries. Inside, the berries usually have a couple of large seeds that are more similar in size and appearance to Oregon grape seeds.
I collected all the fruit for seeds from Garden Fairy Farm’s property. If you want to collect your own seeds and don’t yet have the species you’re looking for, just be conscious of where and what you’re collecting. Make sure that you are collecting from a non-protected public land or a friend’s property. Take only what you need (it’s often suggested to take less than 5% of the available seed) from species that are not threatened or endangered.
Happy berry seed planting, and if you have any questions about starting berry seeds, just ask!