Articles

Vegetable Garden Soil Preparation

These tidy beds have a compost mulch layer protecting vegetables and a walkway protected with thick grass clippings.
These tidy beds have a compost mulch layer protecting vegetables and a walkway protected with thick grass clippings.

Rain and snow melt make spring garden soil preparation a challenge every year, but once you can get into the garden, get into your soil! Feeding your garden soil in spring is an investment that pays off every time. Amending, turning, tilling, fertilizing, and mulching are the five practices needed to make your garden great all season! The addition of drip hoses for easy irrigation can make garden care even more effortless.

Fafard Premium Natural & Organic Compost Blend packAmending Garden Soil

Rich soil yields better crops, so it pays to feed your soil. Adding the best amendments will ensure your soil is ready to work. Adding lots of compost will increase good yields, but be sure that your compost is good quality. Fafard Premium Natural & Organic Compost is a high-performing compost sure to give your garden what it needs. For areas where you intend to plant greens, go with nitrogen-rich amendments, such as Fafard Garden Manure Blend.

Turning Garden Soil

“No till” areas in the vegetable garden need different care.  These include beds with perennial and winter crops, like areas with asparagus, garlic, strawberries, or hardy herbs, as well as well-amended spots that are already in good shape below ground. Still, adding extra organic matter to no-till spots will ensure better growth while allowing for the addition of needed amendments. Adding a layer of compost and lightly turning it into the surface will increase organic matter while not disrupting your plants or soil structure.

Tilling Garden Soil

Compost acts as both an amendment and protective mulch.
Compost acts as both an amendment and protective mulch.

Many gardeners have bed areas that are tilled yearly. This has its pluses and minuses. Tilling brings the bank of weed seeds to the surface and disrupts soil structure and organisms, but it also increases tilth and allows organic matter to be worked deeply in the soil. If you plan to till, plan to double your amendment by adding a till-in layer and a mulch layer. First, put down a thick layer of compost or manure and till it deeply into the soil, then rake and berm bed spaces as needed. Finally add a second layer of compost to further enrich the soil and protect against weeds. The second step is extra important because tilling brings lots of weed seeds to the soil’s surface.

Fertilizing Garden Soil

Many vegetables require lots of food to produce good yields through the season. It’s essential to feed the garden well from the beginning with a good tomato & vegetable fertilizer. OMRI Listed fertilizers approved for organic gardening are best. Simply broadcast the fertilizer and gently work it into the top layers of soil where it’s needed most.  Heavy feeders, such as tomatoes, peppers, and melons, should be fed again at planting time.

Mulching Garden Soil

In addition to adding a compost mulch layer, I protect and define walkways with leaf mulch, straw or hay, and grass clippings. These natural mulches stop weeds and make it easier to traverse the garden in wet, muddy weather. They also hold water and keep root zones cool on hot summer days. By fall’s end, they have usually broken down into accessible organic matter.
Living mulches are another option. Planting a dense summer cover crop in walkways, like white clover, will keep them tidy, cool, and mud-free while also feeding the soil. Just be sure to keep the edges trimmed and turn plants under in fall.

Amendment Application Formula

When adding amendments, determine how many inches you want to add over your garden area. Here is the simple formula needed to determine this:

([area to cover] ft2 x [depth in inches desired] x 0.0031 = ___ yd3).

Example: If you wanted to cover a 20 square foot area with 2 inches of compost, the result would be: 20 ft2 x 2 inches of compost x 0.0031 = 2.48 yd3.

A thick layer of straw helps hold moisture around these okra plants while also keeping walkways clean and weed free.
A thick layer of straw helps hold moisture while also keeping walkways clean and weed free.

Irrigation

For added benefit, consider snaking a drip hose beneath mulch layers to make summer watering easier and more efficient. Below-the-surface watering keeps water at root zones while virtually stopping surface evaporation on hot days. The key is marking your drip lines from above (to keep from accidentally cutting the line with gardening tools) and securing nozzles for easy access. At watering time, just hook up your lines and let them drip for an hour or so to ensure deep watering.
Once the vegetable season takes off, your garden will be in good shape with these five steps. Sure, weeds, drought, and hot days will come, but their impacts will be minimized  and your time and garden’s productivity will be maximized.

Native Wildflowers for the Garden

Spring Virginia bluebells in woodland - April 2007
Spring Virginia bluebells blanket a woodland garden floor. (Image by Jessie Keith)

America’s eastern native plants are a national treasure.  They also offer a wealth of material for American gardens.  This is perhaps most evident in spring, when many of the most beautiful native wildflowers strut their stuff in our fields, forests, or perennial borders.

Bloodroot

Bloodroot
Bloodroot is a very early spring bloomer. (Image by Basefilm)

Among the first of these to bloom is one of the queens of the Eastern forest, bloodroot (Sanguinaria canadensis).  Its broad, scalloped, kidney-shaped leaves unfurl in early spring, sending forth dainty, white, short-stemmed flowers that shatter within a few days of opening.  Far longer lasting, however, are the breathtaking double blooms of the cultivar ‘Multiplex’, whose sublime form would do the finest waterlily proud.  In whatever form, bloodroot makes a wonderful subject for massing and naturalizing in dappled shade.  A moist, relatively coarse soil suits it best (amend heavy or sandy soils with a good compost such as Fafard Premium Natural & Organic Compost).

Virginia Bluebells

Virginia bluebells along stone path
Virginia bluebells have great color and naturalize effortlessly. (Image by Jessie Keith)

Another first-rate naturalizer for moist shade, Virginia bluebells (Mertensia virginica) sends up clusters of nodding, long-necked bell-flowers that morph from pale pink to summer-sky-blue upon opening in early- to mid-spring.  The 15- to 18-inch-tall plants are well furnished with broad, blue-dusted leaves that tone prettily with the flowers.  As bloom fades, so does the rest of the plant, yellowing and dwindling to a thick fleshy rootstock in late spring. Colonies of seedlings often follow.  Wild-collected roots and plants of Virginia bluebell are sometimes sold by disreputable dealers, so buyer beware.

Celandine Poppy

Celandine poppies
Celandine poppies add a golden glow to the spring wildflower garden (Image by Josve05a)

With its sunny yellow mid-spring flowers and penchant for self-sowing, celandine poppy (Stylophorum diphyllum) makes an excellent shade-garden companion for Virginia bluebells.  The 2-inch-wide, crepe-textured, four-petaled poppies are borne atop 18-inch clumps of bold foliage with oakleaf-shaped lobes.  Bristly seedpods resembling miniature gourds ripen in late spring, with dormancy (and enthusiastic self-sowing) ensuing.  Both celandine poppy and Virginia bluebells work well with other, more persistent woodlanders (such as ferns and Solomon’s seal) that fill the gaps left by their early exit.

Woodland Phlox

Although many native woodland perennials die back after blooming in spring, some stay around for the long haul.  These include two species of Phlox that make excellent subjects for borders or naturalistic plantings.  Woodland phlox (Phlox divaricata) produces drifts of fragrant, five-petaled blooms on wiry, foot-tall stems with paired, pointed leaves. The flowers are typically periwinkle-blue, but white, violet, and other colors occur in the wild and in cultivation.  Their form and hue combine effectively with Virginia bluebells, celandine poppy, white trilliums, wild geraniums, and other wildflowers that bloom in mid-spring.  After flowering, plants persist through the growing season and beyond as low semi-evergreen hummocks.

Crested Iris

Yet another splendid spreader for partial shade, crested iris (Iris cristata) grows from knobbly rhizomes that walk along the soil surface, like a bearded iris in miniature.  Fanned tufts of arching, 6-inch, blade-shaped leaves give rise to proportionately large blooms that slightly over top the foliage in mid-spring.  Flower color ranges from violet-blue to white, with contrasting yellow and white markings.   Several cultivars are available.  A lightly shaded site with moist, fertile, relatively porous soil is ideal.

All of these – and many more besides (including Geranium maculatum, Hepatica acutiloba, Trillium grandiflorum, Delphinium tricorne, Tiarella cordifolia, Polemonium reptans, and Uvularia grandiflora) – are essential plants for any eastern North American garden that seeks to embody a sense of place.

Gardening with Azaleas

Rhododendron 'Hinode-giri' (Kurume Hybrid)
Azalea ‘Hinode-giri’ (Kurume Hybrid) is a bright selection for spring. (Photo by Jessie Keith)

A single azalea, cloaked in bright petals, is the essence of spring. Grouped together, these versatile shrubs make an elegant tapestry in semi-shaded areas of the garden. With single or double flowers in white, shades of pink, red, purple, yellow and orange, the artistic possibilities are unlimited. Achieving great garden effects with one or more of the many azalea species and varieties requires little more than knowledge of their basic cultural requirements, a bit of garden or container space, and imagination.

Azalea Basics

Rhododendron 'Josephine Klinger' (Ghent Group)
The sunset flowers of azalea ‘Josephine Klinger’ (Ghent Group) offer luscious springtime color. (Photo by Jessie Keith)

All azaleas belong to the rhododendron genus and have Latin names that begin with the word “rhododendron.” So do their close relatives, the ornamental plants that go by the common name, “rhododendron.” This can cause confusion for novice azalea buyers. Fortunately, differences between azaleas and rhododendrons are fairly easy to spot, even if plant tags are missing. Azaleas are generally small-leafed deciduous or evergreen shrubs with loose clusters of fragrant, funnel or trumpet-shaped flowers. Rhododendrons are most often evergreens with larger leaves and fat trusses of bell-shaped blooms.

Azalea Cultural Requirements

A mature azalea–which can grow anywhere from two to eight feet tall–may look big and strong, but its roots are shallow and need consistently moist, well-drained soil that is on the acid end of the pH spectrum. If you are not sure about your soil chemistry, use a soil test kit, available at nurseries and garden centers, to find out. If soil is neutral or alkaline, amend with a product like Fafard Sphagnum Peat Moss to help increase acidity. Preserve soil moisture by mulching azaleas with at least two inches of organic material, spread in a two-foot radius around the base of each plant. If pruning is needed, do so immediately after flowering.

Azalea Stars for Shade

Pink Rhododendron canescens
The palest pink flowered mountain azalea (Rhododendron canescens) is a great native for the garden. (Photo by Jessie Keith)

In the wild, azaleas are natural understory plants that thrive in light shade. This trait makes them perfect for the semi-shaded or woodland garden, where the colorful blooms lighten things up in mid to late spring. If you have room, plant varieties like fragrant, pink ‘Candy Lights’ in groups of three for a dramatic impact. Underplant azaleas with spring bulbs for early interest and install hosta varieties for color and texture later on. Add foliage color by using a variegated azalea such as the semi-evergreen ‘Bollywood’, featuring green leaves edged in cream.

Native Azaleas

Native azaleas, including the fiery golden-orange flame azalea (Rhododendron calendulaceum) and pale pink flowered mountain azalea (Rhododendron canescens), make excellent additions to native plant gardens. The blooms attract butterflies and hummingbirds, while the fragrance lures human admirers. Place close to paths or seating areas to take advantage of the scent. For a succession of bloom and three-season interest, try combining flame azalea with another native shrub, oakleaf hydrangea (Hydrangea quercifolia), which bears white flower panicles that age to pink and oak-like leaves that redden in the fall.

Container Azaleas

Glenn Dale azaleas at U.S. National Arboretum. (Photo by Tim McCabe, USDA)
At the U.S. National Arboretum, Glenn Dale azaleas flourish. (Photo by Tim McCabe, USDA)

Bloom-a-Thon ‘White’, which tops out at 36 inches tall, is typical of smaller azaleas that work well in large containers. The Bloom-a-Thon and Encore series, like other compact, reblooming varieties, have the added bonus of flowering once in mid-spring and again in early summer, with the possibility of an additional flush of bloom in early fall. For a continual feast of flowers, underplant containers of reblooming azaleas with New Guinea impatiens in complementary or contrasting colors. Containerized azaleas benefit from the good nutrition and water retention provided by a quality potting medium like Fafard Natural and Organic Potting Soil.

Azalea Colors

Sometimes azalea lovers get carried away with color, planting magenta, orange and pink varieties close together. While this may stop traffic in the neighborhood, it also tends to create visual chaos. Make the landscape more coherent by choosing one color or color range, such as pinks. If there is room, plan for a succession of bloom by planting an early blooming azalea, like pink-flowered ‘Camilla’s Blush’ and a later flowering specimen in the same color range. ‘Weston’s Lollipop’ is one example. Underplant with perennials and annuals in the same hue. For a sophisticated finish, add a few contrasting companion plants in a shade that is on the opposite side of the color wheel. ‘Lime Green’ flowering tobacco (Nicotiana alata), for example, makes a perfect foil for a pink planting scheme.

Growing Broccoli, Cabbage, Cauliflower, and Kale Organically

Large-headed cabbages with farmhouse in the background
Large-headed cabbages, like those growing in this spring vegetable garden, need lots of space to reach full size .

Of all the cool-season vegetables, few are as variable and satisfying to grow as cole crops (Brassica oleracea), also called “brassicas”. Tasty favorites like kale, cabbage, broccoli, and cauliflower yield big harvests and are easily grown the organic way, even in the face of lots of pests. It all starts with healthy plants and good care.

Small 'Caraflex' cabbages
Smaller cabbage varieties, like these ‘Caraflex’, can be planted closer together.

Where summers are hot, cole crops are best grown in spring or fall, but in my community garden my spring crops yield better. This is largely due to plentiful foragers, like rabbits, groundhogs, voles, and deer. By summer’s end, mammalian garden pests are in larger numbers and always take a toll on my fall crops—particularly my brassicas. Fencing and smelly organic animal repellants like 100% natural Plantskydd will help, but it’s always a battle.
In spring, it pays to plant large, robust seedling starts for quick establishment and good success. If growing from seed, I begin planting early indoors—generally in late February to early March. By the time my plantlets are 4-inches tall, they are ready to harden off and plant outdoors. Starts are also sold at local nurseries, though they offer less selection. Seed catalogs always have newer, more interesting varieties. This year I chose seeds for the small-headed savoy cabbage ‘Alcosa’, broad-leaved ‘Galega de Folhas Lisas’ kale, bolt-resistant ‘Packman’ broccoli, and bright purple ‘Graffiti’ cauliflower.

Fafard Premium Natural & Organic Compost Blend pack
Fafard’s OMRI-Listed Compost Blend is an ideal amendment for cole crop beds.

Growing Brassicas

Brassicas require full sun for best growth. Deep, fertile soil with a slightly acid to neutral pH (6-7) is ideal. Be sure to amend the soil with Fafard® Sphagnum Peat Moss and Premium Natural & Organic Compost —being sure to till amendments in deeply—and fortify with a fertilizer formulated for vegetables. These vegetables have high macronutrient requirements (NPK 14-14-14) and specific micronutrient needs (high calcium and boron). At planting time, I recommend fertilizing with an OMRI-Listed (certified by the Organic Materials Review Institute) vegetable fertilizer, bone meal, and borax, at the recommended doses.
Set plants out after hard frosts have ended but cool days and light frosts are still expected. Most cole crops can withstand freezing temperatures down to 20° F but grow best at temperatures between 70° and 85° F. Late March to early April is the best planting window where I live in the Mid-Atlantic.
Each brassica grows a little differently and may require slightly different care. Here are the growing basics for my spring standbys:

Growing Broccoli

Broccoli varieties vary widely. Some produce enormous central clusters and others smaller clusters with ample side shoots; some have large, loose beads (buds) while others have small beads produced in tight, dense clusters. Gardeners can expect plants to bear heads 50 to 70 days after planting. ‘Packman’, ‘Diplomat’, and ‘Early Purple’ are three high-performing varieties that produce big heads, have good side shoot production, and grow beautifully in spring.

Brassica oleracea 'Early Purple' (Italica Group)
Grown for its good looks and flavor, broccoli ‘Early Purple’ is also a popular market vegetable.

Broccoli seedlings look like nondescript leafy sprouts, but in a matter of months they will produce big budding heads of broccoli. Space your broccoli plants about 1 to 1.5 feet apart at planting time, and plant a minimum of six plants for good yields. Don’t allow newly planted seedlings to dry out, and ensure established plants always get ample water. Once nice broccoli heads are set, harvest them and wait for more to develop. Broccoli is a cut-and-come-again crop that should not be allowed to flower and set seed. I generally harvest mine with garden shears or a garden knife.
There are a couple of troubles specific to broccoli. Boron deficiency causes florets to turn brown prematurely and stems to become hollow. Additionally, insufficient water will keep plants from setting florets, and heat in excess of 86 ° F may encourage plants to bolt quickly and taste bitter.

Growing Cabbage

There are lots of fun cabbage varieties offering different flavors, looks and characteristics. Heads may be conical, flattened, rounded, large or small, and can have smooth or savoyed leaves. Four varieties for connoisseurs are the blue-green and purple-pink blushed ‘San Michele’, dwarf conical ‘Caraflex’, giant sweet savoyed ‘Drumhead’, and elongated purple ‘Kalibos.’ Days to harvest vary from variety to variety , but on average you can expect heads to develop 63 to 88 days after planting.

'Alcosa' cabbages
‘Alcosa’ is a small, savoyed heirloom cabbage that’s easy to grow.

Seedlings should be planted outside when they are around 4 to 6 inches tall. Compact varieties may be spaced as close as 10 inches apart and large varieties between 18 and 24 inches apart. Once healthy heads develop, cut them at the base with a garden knife and remove any large, ratty lower leaves. Cabbage will store for a long time, if refrigerated or kept in a cool dry place.
There are several common cabbage nutrient deficiencies. Potassium deficiency is common and results in heads with leaves that become yellow then dry and papery along the edges. If comparable yellowing is seen between the leaves, then magnesium deficiency is likely the problem. Heads with weak or hollow stems are suffering from boron deficiency.

Growing Cauliflower

Cauliflower comes in a myriad of sizes (tiny to giant) and colors (white, green, purple and orange). Fun, interesting varieties include the dwarf heirloom ‘Snowball’, bright purple ‘Graffiti’, electric orange ‘Cheddar’, and very large ‘Giant Naples.’

Brassica oleracea 'Cheddar' (Botrytis Group)
The orange cauliflower ‘Cheddar’ is higher in beta-carotene than white forms.

The sooner you can get your cauliflower into spring ground, the bigger the heads will be, but it’s important to note that this brassica is not as frost-tolerant as cabbages, broccoli and kale. Seedlings should be planted 18 to 20 inches apart. Be sure to give plants ample water when cauliflower heads begin to develop. Layers of leaves cover and protect developing heads from sun and pests. Once the leaves unfurl and heads look curdy and fully developed, they can be cut from beneath and harvested.
Nutrient deficiencies and heat troubles that plague broccoli are also a problem with cauliflower. Excessive heat and ill-timed harvest can cause heads to elongate and taste bitter.

Growing Kale

Some of the best kale varieties for eating are the popular ‘Nero di Toscana’ (aka. dinosaur kale), heat-tolerant Portuguese ‘Tronchuda Beira’, and frilly, tender ‘Red Ursa’. Young leaves can be eaten fresh in salads and more mature leaves are great for cooking.

Brassica oleracea 'Lacinato' (Acephala Group)
One of the most beautiful and delicious kales for the garden is the blue-green ‘Nero di Toscana.’

Kales are cold hardy and can be planted along with broccoli and cabbage starts. Spacing varies from variety to variety, but on average 12 to 18 inches apart is a good planting range. Leaves can be harvested as soon as plants reach a reasonable size and have ample foliage. Harvest leaves as needed using clean shears.
Unlike the other cole crops mentioned, kales can survive hot summers with care. Be sure to water them well through the hot months while protecting them from summer pests, namely harlequin bugs and cabbage loopers.

Brassica Pests

Lots of pests predate on brassicas. Slugs and cabbage loopers (Trichoplusia ni) commonly attack cabbage heads, eating their way through the layers of leaves. Harlequin bugs (Murgantia histrionica) are aggressive sucking insects known to lay waste to summer kales, and cabbage maggots (Delia radicum) will de-root and gut spring plants in no time.

Orange, black and white harlequin bugs attacking a head of 'Packman' broccoli.
Orange, black and white harlequin bugs attacking a head of ‘Packman’ broccoli.

There are several organic methods to tackling these pests. Sluggo® is a non-toxic, OMRI-Listed pesticide that will quickly take care of slugs. Cabbage loopers are best tackled with a product containing BT (Bacillus thuringiensis); OMRI-Listed Safer® Caterpillar Killer is a great choice. Harlequin beetles are eradicated at all stages with products containing neem oil, a popular organic pesticide, and applying a sprinkling of wood ashes around the base your brassicas will deter cabbage root maggots.
It also pays to recognize and destroy the pest eggs on sight: Small, pearly cabbage looper eggs are laid singly or in small, open clusters (5-7 eggs) on leaf surfaces; harlequin bug eggs look like black and white bulls-eyed barrels laid in tight clusters (~12 eggs) along leaf undersides; cabbage maggot flies lay eggs near the base of plants, so it can be helpful to sink 3” plastic bottle collars (1” below ground, 2” above) to keep hatched maggots from reaching seedlings.
With good care, any gardener can grow broccoli, cabbage, cauliflower and kale organically. Once the harvest begins, it will make all the work worth it.