Gardeners rejoice! In addition to swaths of cherry blossoms and daffodils, March brings the long-awaited arrival of spring to Portland — and the rest of the Northern Hemisphere, for that matter. This year the vernal equinox falls on Tuesday, March 19, marking the beginning of the astrological season. (Although if you ask a meteorologist, spring starts on the first of the month.) No matter whose reckoning you go by you, this month is time to get back into the swing of things in the garden and begin putting into action all of the plans you dreamed up over the winter.
Putting Shovel to Soil
Although our soils don’t tend to freeze with any great regularity here, come March, the ground in Portland is more workable than it has been in months. Coupled with the rains that continue to fall, this makes it a great time to plant shrubs, trees, and a variety of perennials and annuals, giving them plenty of time to get established in your garden. Savvy gardeners will tell you that the best time to shop for spring-blooming woody plants is early in the season because once they begin to flower, they don’t tend to stay on the floor for long! At the Farm, our best selection of budded-up magnolias, rhododendrons, and more can generally be found early this month, and getting ahead of bloom time means you’re sure to enjoy the full course of a plant’s bloom cycle in your garden, from that first flush of flowers to the final fallen petal. With this said, it’s important to keep a watchful eye towards the forecast and be careful to protect any frost-tender plants or plants with fattened buds if temperatures are anticipated to dip below freezing, which can still happen from time to time in March.
If you like to direct sow flowers, now is a great time to spread seeds for many different flowering annuals and perennials, including Bachelor’s Buttons, California Bluebells, and Love-in-a-Mist, as well as many species of lupine, sweet pea, poppy, coreopsis, and larkspur. (For a more complete list of plants that can be started now in our climate, check out Oregon Tilth’s Maritime Northwest Garden Guide, which we highly recommend to anyone gardening in our area!) If you plan on weeding and mulching your garden beds — a stellar idea, if you ask us — just be careful not to mulch over any areas where you have broadcast flower seeds. A layer of mulch or compost may keep them from germinating along with the weeds.
Apart from these tasks, you can help your plants out by dividing dense-growing perennials such as bee balm, chrysanthemums, persicaria, and phlomis to refresh them and keep their size in check. You can also support healthy new growth on your shrubs with an application of organic fertilizer. For most shrubs, E.B. Stone Tree & Shrub Food will do the trick, but for acid-loving species, try E.B. Stone Rhody, Azalea, & Camellia Food, which also happens to work great for blueberries!
Pruning Back
As we prepare for most plants to push out a flush of new spring growth, March is perfectly positioned for gardeners to do a little pruning in the landscape. This is especially true for herbaceous ornamental grasses; while the previous year’s growth can provide wonderful structure to the winter garden, it can be cut back before spring arrives for a tidier appearance. If you wait until too late in the season to give your grasses a haircut, you risk cutting the first shoots of new growth along with the old and setting your plants back, so earlier is better.
In addition to more typical pruning to improve the shape and size of shrubs, those affected by winter weather can be pruned to remove any severe damage. Spring growth should help to cover your cuts in the months to come.
Kitchen Gardening
As with the rest of the garden, early spring is the time to get back into the Kitchen Garden, but be careful not to get ahead of yourself! While the warming March air might tempt you to fill your beds, it’s still too early to set out warm-season crops like tomatoes, eggplants, and peppers. However, if you know you plan to grow these heat-loving crops, you can go ahead and start them from seed indoors. Electing to grow plants from seed is not only rewarding and cost-effective, but it offers you access to many more varieties than you will find as starts later in the season — even in an exceptionally-stocked Greenhouse like ours! If you want to get a head start on the growing season, cold frames are another great addition to the Kitchen Garden, giving you a place to start seeds and harden off transplants outdoors.
With that said, many cool-season crops can be sown directly in the ground in March, and larger fruiting trees and shrubs can also be added this time of year. We have a greenhouse full of cool-season vegetable starts, bare-root veggies and berries, seed potatoes, and more! In addition to blueberries, currants, elderberries, strawberries, and cane fruits like raspberries, early spring is the best time to plant fruit trees such as figs, pomegranates, persimmons, apples, and pears. Or, for something more unique, consider planting an olive tree or flowering almond!
If you haven’t pruned your existing fruit and nut trees or treated them for diseases, there’s still time to do so before they leaf out. We have a full guide on winter orchard tasks to set yourself up for a bountiful harvest later in the growing season. And to make sure your fruit trees are properly pollinated, don’t forget to set up a Mason Bee house before the flying season. (We have an article on that, too!)
Among all the tasks there are to do this month, most of all, remember to take some time to bask in the sun and enjoy the return of spring.