Gardening is a year-round treat, but the arrival of spring is special, because it’s the moment when both the gardener and all the plants in the yard are bursting with excitement.
The next several weeks mark not only the time when we launch the growing season, but also the period when plants are at their most vulnerable. Fresh growth is tender and can be damaged by the wild swings in weather in April and May. There isn’t much you can do about damage due to a severe storm, but there are measures you can take to help the garden survive the more normal weather ups and downs. These tasks also give you a chance to get outside to greet and enjoy the spring.
You will need fresh supplies of plants, soil mixes, fertilizers and tools. This might be a concern in the time of coronavirus restrictions, but many garden centers, hardware stores and feed stores operate outdoors for the most part. And, of course, there’s that bazaar known as the internet.
Cleanup and bed preparation
In beds free of permanent plantings, such as the vegetable garden and annual flower beds, the tasks are straightforward. The first job is to remove weeds. Forget the impending dandelions and violets; I’m talking about established winter weeds, whose roots now go deep — interlopers like henbit, chickweed, bittercress and ground ivy. You rarely need herbicides for this; the weeds will lift quite easily between your fingers in the rich, moist soil of the veggie patch. They will also surrender to a weeding knife or a sharp, long-handled hoe. Get to them before they go to seed.
Weed seeds will germinate any time the soil is disturbed, so weeding is not an annual event; it is a way of life. By sowing desired seeds in a straight row, you can more easily spot the gate-crashing weed seedlings for rapid removal.
All the dead carrots, kale stalks and other lingering detritus of last season should also be removed as you work the soil.
The soil will be compacted by snow and rain, and it will need fluffing up. The easy way to do this is with a three-pronged cultivator, though I prefer to turn the bed with a garden fork, which gets deeper. After scuffing up the soil, add a layer of fresh material to the bed and work it in. You can use your own screened compost or bags of soil amendments. I like to use purchased composted leaf mold and aged manure, which, in my experience, are reliably free of weed seeds. Water the newly prepared bed and wait a few days for the soil to settle before seeding and planting.
In permanent plant beds, the cleanup needs a more delicate touch. When removing weeds, take care not to damage the emerging growth of bulbs and perennials. Hand-pulling is a good option, or use a small, sharp knife to get into tight spots.
Remove any accumulated winter-blown leaf litter from under bushes and hedges, and cut back any remaining dead stalks of last year’s perennials and grasses, again being careful around emerging shoots. The soil will benefit from a little cultivation and a top dressing of compost or leaf mold, which is then scratched into the soil. These beds also should be mulched.
Once trees and shrubs have broken into flower and leaf growth, they are prone to cold damage, because the tissues are soft and tender. It pays to keep an eye on nighttime temperatures into mid-May. If a frost or near-frost is predicted, you can cover certain plants for protection. The Hortensia hydrangeas are a good candidate for this, as are Japanese maples. The blossoms of strawberries and blueberries should be covered against freezing, as well as those of apples, peaches and persimmons if the trees are small enough to wrap.
Seedlings of veggies, herbs and annuals should be covered on such nights.
If you don’t have horticultural row fabric, you could use a light sheet. The challenge is ensuring the covering won’t blow off (clothes pins are handy), and don’t use anything that will crush small plants.
Seeding and hardening off
We start young plants in two ways: either by seeding directly into the garden or planting small transplants that are a few weeks old. Some seeds can go directly into the ground now, including peas, radishes, carrots, nasturtium and lettuce, but wait until the soil has warmed, until at least mid-May in the Pacific Northwest, for sowing (or transplanting) warm-season vegetables and summer annuals.
The process of conditioning transplants for the spring garden is called hardening off. If you don’t do this, plants will probably wilt and die — or at least fail to thrive. Even if you buy transplants, there’s no guarantee that they have been adequately conditioned, so you should harden them off to be sure.
During the day, place the pots outside in a sheltered area, away from the wind and afternoon sun. Bring them in at night. Water them at least once daily, before they wilt. Do this for a week before planting, longer if cold temperatures are in the forecast.
Cold is not the only problem. After planting, transplants should be protected from sun and wind, at least for their first 24 hours, with horticultural row covers or shade cloth. If that is not an option, plant on a cloudy or rainy day.
Transplants of hardier plants, such as cabbages, broccoli, parsley, lavender, cilantro, nasturtium and pansies, are happy to be planted in April. Warm-season transplants, such as tomato, pepper, squash, cucumber and basil, need the warmer soils and temperatures of late May. Don’t be in a rush to plant them, even if they are available (too early) at retailers.
A light layer of mulch, no more than two inches, is helpful in suppressing weeds and retaining soil moisture. But mulch should not be viewed as a cosmetic covering for our benefit; it is there for the plants’ needs. Mulches that are applied too thickly or too often will harm plants and the soil. I prefer fine-textured, organic mulches, such as pine fines. Save wood chips for paths. Avoid mulch volcanoes around trees, which cause harmful root growth and other problems.
If you need acres of mulch every spring, it’s because you don’t have enough ground-covering plants.
It may be impractical to plant every vacant bed in the yard at once, but you could start this spring by tackling an area that is, say, 10 feet by 10 feet. Plug plants take a couple of years to fill in, but they offer a more affordable way to plant en masse.
It’s best to plant most trees and shrubs in early fall, because they are not then putting energy into top growth while dealing with transplant shock. Spring-planted woodies need handling with more care, and the earlier you can plant them, the more established they will be before summer.
Most trees and shrubs are container-grown and may have congested roots that need teasing out and trimming, so there is always a degree of root manipulation and damage when planting. Be gentle, and make sure the tree or shrub is set at the correct height and that the backfilled soil is packed firmly. A good soaking at planting time is in order, and plants should be watered periodically, especially if the weather turns dry, but the roots should not be kept wet.
The principle of handling roots gently applies to perennials and annuals, too.
Any lawn will look better after it’s given a sharp edge where it meets plant beds. Use a spade or long-handled edging tool rather than a shovel, if possible.
Generally, grass is best kept at a somewhat tall 3 inches to reduce stress, but mow it before it gets more than 4 inches in height. This may mean having to mow twice a week in April and May. Replace or sharpen dull mower blades.
Pre-emergent herbicides are available to deal with crabgrass and Japanese stiltgrass, but the best way to minimize lawn weeds is to have a thick stand of turf. Dandelions and other weeds can be hand-dug or given a spot treatment of weed killer.
Lawn fertilizer should be applied at half the normal fall rate in spring to reduce nutrient runoff, but check the rules where you live; some jurisdictions limit fertilizer and pesticide use on home lawns.
The optimal time for seeding with fescues is late summer and early fall. Bare patches can be seeded now with proper soil preparation, but the new grass may melt away in summer heat. Similarly, fresh sod also needs soil preparation and may not make it through the summer, but it will look good for a few weeks, at least. Consider converting a part of the lawn into plant beds.
Old soil and plant material should be cleaned out; the soil can be spread around the garden, and pots can be scrubbed with a bleach solution to sanitize them and send any slugs on their way. It’s best to use fresh potting mix. To make it go farther, fill the bottom half of the pot with your own compost. Any weed seeds in the compost will be safely buried.
Containers must drain. Make sure the drainage holes are not blocked, and don’t put a saucer underneath. The same hardening-off rules apply to container plants.
Plants get a boost from fertilizer, but check the ratio of key nutrients — nitrogen, phosphorus and potassium — to see if it matches the plant you’re feeding. Slow-release feeds are useful in container plantings. Granular fertilizer can damage plant tissues. Generally, I prefer organic fertilizers, such as kelp meal, fish emulsion and plant feeds made from livestock byproducts. They are gentle on plants and help to sustain soil biology.