perennial vegetables

APRIL NOTES

Standard

primula-veris.jpg

APRIL GARDENING CALENDAR GENERAL

This winter was a “longie” with lots of snow, a situation which voles love!   In our market garden we discovered damage from voles on Campanula medium (Canterbury bells)—just the ones stored in pots in sawdust, but not those in the ground.  Also some potted Primulas, strawberries, and Echinaceas were completely eaten.  It was the same case with these last few; plants in the ground were unharmed, those in pots in sawdust were eaten.  It may be because plants all stored together serve a sort of “banquet” for voles, while those in the ground, mixed in with other plants are harder for the little critters to find.  I am experimenting with inter-planting Fritillaria imperialis (Crown Imperials) with plants that tend to be vole favorites, to see if they will help deter them.  Fritillarias are very odorous, and rodents do not eat them. 

April tasks:

Finish pruning and grafting of fruit trees if not already done.  Plant grapes and other fruiting perennials, shrubs and vines; fertilize and prune raspberries and blackberries.  Start many flowers inside for transplanting out and direct sow the last hardy annuals.  Direct sow many vegetables late in the month and into May.  April is characterized by ups and downs in temperature—watch for frosts!  Protect frames at night and admit air daily.  Place row covers on newly transplanted, slightly tender plants. 

VEGETABLES

If not done already, sow indoors, for transplanting out early in the month: basil, cabbage, celery, tomatoes, broccoli, cauliflower, kohlrabi, head lettuce, artichokes, Brussels sprouts, Asian cabbage, leeks, greens.  After the 15th, sow watermelon, cantaloupe, squash, pumpkins and cucumbers into peat pots for easy transplanting. 

Direct sow these outdoors once weather permits and soil temperatures are above 45 degrees:  beets, arugula, carrots, caraway, celery, chervil, chives, cilantro, dill, fennel, thyme, oregano, sorrel, collards, mache, fava beans, cress, Jerusalem artichokes, kale, kohlrabi, cabbage, cauliflower, leeks, lettuce, mustard greens, rhubarb, turnip greens, onions, parsley, parsnips, peas, potatoes, radishes, salsify, scallions, spinach, Swiss chard.  Sow corn (after the 20th). 

Harden-off vegetables in frames, or by exposing them outdoors a few hours at a time.  Transplant the following hardy vegetables outside around the middle of the month (they can take some light frost): asparagus, broccoli, cabbage, cauliflower, Chinese cabbage, endive, leeks, lettuce, onion sets and plants, Asian greens, parsley.  

FLOWERS

Sow indoors April 1 for transplanting out: Chinese asters (Callistephus), Cerinthe, Celosia, Craspedia, Calendulas, annual Centaurea, Cleome, Cosmos, Cynoglossum, Eragrostis, Panicum, Pennisetum, and annual grasses.  Late in the month: sow zinnias indoors. 

Direct sow outdoors all month: annual alyssum Lobularia maritima), Bupleurum, carnations, pinks, sweet Williams, Cynoglossum, stocks, rose campion, wall flowers, Lychnis, lupines, lavateras, columbines, valerian, polyanthus, auriculas, Canterbury bells, hollyhocks, honeysuckles, rockets, honesty, fox gloves, snapdragons, sweet peas, poppies, larkspur, cornflowers, nigella, Lavatera, poppies, valerian, kiss-me-by-the-garden-gate, dill, morning glory, sweet peas and wildflowers.   

Weed and clean borders.  Divide perennials early in the month: carnations, Bellis, Achilleas, Asters, mums, Campanulas, Centranthus, Coreopsis, Dicentra, Dodecatheon, Echinops, Euphorbias, Gauras, Gaillardias, Gentians, Helianthus, hellebores, daylilies, Heucheras, Hostas, Lobelias, Papavers, Oenotheras, Phlomis, Monarda, Liatris, and Marrubiums. 

Start dahlia tubers this month and make cuttings if possible. 

Shade auricula primroses from intensifying spring sun.   This is when auriculas need the most water, but remember— never waterlog the compost.  The month of April is their peak bloom period and hybridizing can take place now.  Shows are held this time of year. 

FRUIT

By April 15, finish pruning /grafting/planting fruit trees; spray Bordeaux mix on fruit trees suffering from fire blight; check fruit trees for pests.  Spray superior oil on dormant trees (before leaf out).  Lime-sulfur will control anthracnose or blight on raspberries if applied when the buds first show silver, or on currants and gooseberries at bud break.  Wait three weeks if you decide to spray lime-sulfur (use caution) as a fungicide on roses, lilacs, dormant shrubs, fruit trees, evergreens. 

Weed fruit trees, strawberries, cane fruits.  Set out apple pest traps two weeks before bud break.

TREES, SHRUBS AND ROSES

Lay out lawns by either direct-seeding or purchase turf and roll it out.  If the weather gets windy and dry, water your new lawn frequently. 

Finish transplanting roses and other shrubs (the earlier the better).  Prune established roses after severe frosts.  Cut out all dead and crossed wood, and seal the cuts with water-based glue to prevent the drilling wasps from destroying canes.   Dress rose plants with Epsom salts, wood ashes, compost, manure, alfalfa meal, bone meal, kelp meal, bunt earth, spent hops, etc. , but keep fertilizers 2 inches away from the canes at the base of the plant.  

 

SOIL PH FOR GROWING VEGETABLES

Standard

FullSizeRender

 

Soil pH is a measure of acidity or alkalinity.  This measurement can range from a very low pH of 1.0 to an extremely high pH of 14.0.  7.0 is considered neutral and several vegetables will thrive in soil with a neutral pH.  Some vegetables do prefer a more acidic soil while others prefer a more alkaline soil.  Fortunately most will grow and produce well in a pH range of 5.5 to 7.5.   Areas with high rainfall, such as coastal Washington, tend to have acidic soils high in organic matter, while areas with lower rainfall, such as most of the mountain valleys in Montana, tend to have alkaline soils low in organic matter.  Here in the valleys of the Flathead region, where most of us garden, soils tend to be somewhat to highly alkaline.

Before you amend your existing soil to plant vegetables it is a good idea to test the pH.  An easy way is to purchase a test kit.  Most of them are easy to use and give fairly accurate readings.  Your county extension agent can do a soil test also.  Once you have determined your soil pH and which crops you intend to grow, you can amend your garden soil.  Adding lime will increase pH and make acidic soils more alkaline; adding sulfur will lower pH and make soils more acidic.  Organic matter usually helps reduce alkalinity.  Aged manure, pine needles, compost and coir dust are a few amendments that will help do this while they improve soil structure and encourage beneficial soil micro-organisms.  If your garden is divided into separate beds or raised beds, it is easier to adjust the soil in each bed for what you plan to grow.   I rotate my vegetable crops in a four-year rotation plan, so I try to keep a basic soil pH around 6.0 to 6.5.  This way I can grow almost every vegetable, but I slightly adjust pH each year before growing a particular plant.  For example, I add sulfur before growing potatoes.  Conversely, I add a small amount of lime before planting any of the Brassica family (Broccoli, Brussels sprouts, cauliflower, etc.).   Having soil pH correct for each crop will reduce pest and disease problems as well as increase yields.

Here is a listing of pH tolerance ranges for specific vegetables.  (The optimum pH for each is usually the median between the two extremes.)  I have listed vegetables preferring more acidic soils first and those preferring more alkaline soils last:

Potatoes, 4.5-6.0; sweet potatoes, 5.6-6.5; horseradish and rhubarb, 5.5-6.8; butternut squash, carrots, corn, eggplant, lettuce, peanuts, peppers, pumpkins and watermelon, 5.5-7.0; cucumbers, garlic, winter squash, and tomatoes, 5.5-7.5;  celery, 5.9-6.9; soybeans and strawberries, 6.0-6.8; onions, radishes, shallots and spinach, 6.0-7.0; beets, any of the Brassica family, peas, summer squash, Swiss chard, and zucchini, 6.0-7.5; okra, 6.0-8.0.

 

April Gardening Calendar

Standard

photo (133)

April is another busy month for gardeners; usually a month characterized by ups and downs in temperature.  Keep watch for frosts; protect cold frames with mats if frosts are imminent, and admit air daily as weather permits.  Finish pruning fruit trees if not done, plant grapes; fertilize and prune blackberries.  Check your fruit trees and roses for pests as soon as they bud and leaf out and set out apple pest traps two weeks before bud break.  Weed and amend all your beds now while it is cool and moist.

Finish planting fruit trees, shrubs, roses, and perennials.  This month is a good time to direct sow (where they are to flower)seeds of several flowers: sweet alyssum, cornflowers, carnations, pinks, poppies, stocks, rose campion, Lychnis, columbines, valerian, honesty, foxglove, snapdragons, mignonette, larkspur, kiss-me-by-the-garden-gate and four-o’clocks.  Perennials still may be divided if weather has not become too warm.  Violets can be divided after blooming and cuttings taken of pansies.  Make cuttings of chrysanthemums, gauras, Helianthus, lupines, Lychnis, Liatris, knautias, saponarias, scutellarias and veronicas.  Dahlias and tigridias may be started inside in cold climates and planted out later after frosts are over, or planted outside if the soil temperature is above 60 degrees F.

Several vegetables can be direct sown if weather permits and it is not too cold: beets, arugula, carrots, caraway, celery, chervil, chives, cilantro, dill, fennel, collards, mache, fava beans, cress, kale, Jerusalem artichokes, kohlrabi, leeks, lettuce, mustard greens, rhubarb, turnip greens, onions, pasley, parsnips, peas, potatoes, radishes, salsify, scallions, spinach and Swiss chard.  Sunflowers and tomatillos can be sown two weeks before the last expected frost.

Corn may be sown after April 15th in cool maritime northwest climates, or a week or two later in the inland and mountain areas.  Usually corn is sown about 10 days to two weeks before the last frost.  Native Americans of the Hidatsa tribe living in the Dakotas planted sunflowers first, then corn, and after frosts followed with beans and finally, squash.  Sunflowers were grown by themselves in a field, but corn, beans and squash were grown together; with corn in hills of 6-8 and beans and squash vining through.

Vegetables started last month indoors may be planted out this month: the brassicas, parsley, Asian greens, rhubarb and tomatoes; once frosts are over.

Prune established roses before bud break and seal the cuts with water-based glue or wood glue.  This prevents drilling wasps from injuring the canes.  Fertilize organically with Epsom salts, manure or compost, bone meal or rock phosphate, alfalfa meal and seaweed or wood ashes.

A few things maybe grafted now: grapes, hollies, pears, maples, pines and clematis.  Layers can be made of Cotoneaster, Cotinus, Hydrangea, Lavandula, Lonicera and Parthenocissus. 

Enjoy spring!

Growing Asparagus

Standard

photo (119)

Asparagus (Asparagus officionalis) is a popular vegetable today and was quite popular in the nineteenth century.  The photograph above is of an antique variety, ‘Giant Asparagus’ an engraving from The Illustrated London News, dated 1851.  An asparagus knife is shown alongside the plant.  This year, I grew another old variety of asparagus from seed, ‘Connover’s Collosal’, dating to the second half of the nineteenth century.   It is difficult to find plants of heirloom varieties of asparagus, so one has to start them from seed.  However, the process is slow, as the plants take three to four years to reach the size for harvesting.  (If too many shoots are cut from very young plants, productivity may be reduced, or the plants may die.  But if the plants are allowed to become established, an asparagus bed will last twenty years or more, even up to fifty years!)

Late March into early April is an excellent time to start asparagus from seed.  Use a sterile medium, cover the seed about 1/4 inch deep and place the pots in a warm location (77 degrees is optimum).  The seeds should come up in about ten days.  You may direct seed into a bed if soil temperatures are above 50 degrees, it will just take a little longer for the seeds to germinate.  Asparagus plants begin to grow slowly and will not be ready to transplant out for about three or four months.  Meanwhile you can prepare a bed for them.  An ideal spot is in full sun with a bed large enough to accommodate the number of plants you need.  It is usually recommended to plant five to six plants per person.  Since the plants are perennial (USDA climate zones 4-9) they benefit from a well-prepared bed.  Peter Henderson, in his book Gardening for Profit published in 1867, recommended planting transplants nine inches apart in rows three feet wide for commercial growers, or two feet wide for home gardeners.

Once you have established how many plants you need, you can make the planting bed.  Henderson recommended trenching the bed two to three feet deep with about three inches of rotted manure mixed into the soil.  A deep sandy loam is best for them as they are native to alluvial soils.  Bernard Mc Mahon, in Mc Mahon’s American Gardener, published in 1857, recommended double digging two spades deep and placing several inches of rotted manure in the trench, then spreading another layer of rotted manure over the surface.  He directed gardeners to mix this second layer of manure with the soil to a depth of eight to ten inches.  My young plants, now a year old, have spears a little larger in diameter than a toothpick.  The young plants may be grown in a temporary (sunny) rich bed for another year, then moved to their permanent location.  Place the crowns of the plants two inches below the soil surface.  Keep the beds weeded to ensure quick, even growth.  Mc Mahon recommends three years from planting (which would be four years from sowing seed) before cutting can begin.  Dress the bed every spring with rotted manure, bone meal and wood ashes.

If your family really enjoys asparagus, plant more than five plants per person; I plant twelve per person.  If you plant two-year transplants, spread the roots out like the spokes of a wheel and cover with about one inch of prepared soil.  Water well.  As the plants grow, cover them with more soil until you have them two inches under.  Do not use fresh manure as it will burn them and (heaven forbid) do not use chemical fertilizers, especially on newly planted asparagus.  Wait two years to begin cutting.  A summer mulch of three inches of straw is excellent, will protect the plants in winter and the spears will come up earlier in the spring if the ground is not frozen too deeply.

When you cut asparagus spears get them into the refrigerator right away or cook them immediately because they lose flavor as quickly as sweet corn does.   Considering how expensive asparagus is, I find the start up work well worth while.  Enjoy!