NOTHING SAYS SUMMER like a bowlful of juicy berries. Likewise, nothing says fragile like a fully ripe strawberry or a precious pint of raspberries from the grocery store or farmers market. Which is why many of us think berries are worth the precious ground they occupy all year for a few fleeting weeks of a delicious harvest.
Good news: Even if your beds are reserved for seasonal crops and your borders are filled with perennials, roses and other ornamental plantings, backyard berries can be grown in window boxes, hanging baskets and pots. I asked backyard berry expert Tara Austen Weaver, author of “Growing Berries and Fruit Trees in the Pacific Northwest” (Sasquatch Books, 2019), for tips on cultivating these summer jewels in a container setting.
“The benefit of [growing in] pots is that you won’t have to weed much, if at all,” Austen Weaver says. “And the slugs are not likely to eat your strawberries.” Birds are another matter — they like berries as much as we do. Protect your harvest by netting your plants, in the ground or containers, as berries ripen.
Let’s start with plant selection. Some berries are better suited to growing in containers than others. Fortunately, plant breeders are developing berry plants that have a dwarf growing habit and adapt to living their best life in a container. Even better, many of these varieties are also handsome plants that pull their weight aesthetically as well as productively. Austen Weaver recommends Sunshine Blue blueberry and Raspberry Shortcake, two dwarf varieties that thrive in containers. “Strawberries are all generally good in containers,” she adds.
Plants sorted; let’s talk about pots. “You’ll likely need a larger pot than you think,” Austen Weaver says. “Plants want to grow.” Bigger plants, more berries — makes perfect sense. “Whatever size plant you bring home from the nursery should be immediately repotted into a pot twice that size,” she adds. A 24-to-26-inch pot or a large stock tank will accommodate healthy growth for a good long while. Remember, drainage in containers is essential; roots rot and plants die in soggy soil. Austen Weaver likes long narrow stock tanks for raspberries because the plants’ roots and subsequent cane growth “have room to wander.” A 4-foot-by-2-foot stock tank also will accommodate two dwarf blueberry bushes.
Austen Weaver advises gardeners to stick to one variety of raspberry in each container. “Blueberries, however, are most productive if grown in proximity to a different blueberry cultivar for pollination (not in the same pot),” she adds. While many container varieties are self-fertile, you’ll get even more fruit when you grow more than one variety.
Caring for container-grown berries is similar to cultivating an in-ground crop. The plants will need to be pruned and fertilized to maintain vigorous growth. Keeping plants watered is critical to producing juicy berries. Because container plantings dry out quickly, you’ll need to monitor soil moisture carefully. “Even when we get rain in the summer, check the moisture level in your pots,” Austen Weaver advises. “The amount of water needed will fluctuate depending on the weather and the week.” Automatic irrigation systems should be monitored, and possibly adjusted, throughout the summer. “Make sure you have a plan for when you go on vacation,” she adds.
Austen Weaver keeps her container-grown berries on a deck right off the kitchen, where it’s easy to water plants using recycled rinse water from summer produce, grains and beans. And, I’d imagine, handy for harvesting plump, ripe berries as well.