Now that everyone has their vegetable and flower gardens planted, I think it would be appropriate to talk about garden insects and their control.
The University of Alaska Cooperative Extension service has a booklet "Controlling Vegetable Garden Insects." It is worth having. Richard "Skeeter" Werner, an entomologist at the University of Alaska, gave a lecture last winter to some serious gardeners. I will try to pass on some of his knowledgeable information.
Below-ground insect pests such as root maggots, cutworms or wireworms can be a real nuisance. Onions, radishes, cabbage broccoli, cauliflower, Brussels sprouts, turnips and beets can be plagues with root maggots.
* Adult flies lay eggs at the root collar area of the plants; eggs hatch into white maggots, which feed in tissues of the plant stem and the roots. Plants are weakened, the leaf tips turn yellowish white and the plant dies. You can treat the rows before planting with granular Diazinon or liquid spray Diazinon. Wood ashes, old sawdust, rotenone, diatomaceous earth, or aluminum foil collars around the root collar is also effective.
Plant mint, thyme or hyssop next to cole crops to reduce root maggot infestations. You should rotate these crops throughout your garden area from year to year, since the pupae stage will overwinter and cling to the old plants. Needless to say, it is a good idea to get rid of old plants in the fall to avoid spring infestations.
* Cutworms are another story. Adult moths lay eggs on the leaves of host plants. The eggs hatch in late summer and the larvae overwinter in the ground. The larvae feed on the stems and cotyledons of newly emerged seedlings of peas, beans, squash, corn and cole crops.
To prevent the larvae from biting through the stem, place a rigid object such as a stick, nail or heavy-gauge wire next to the young plant immediately after emergence. Place aluminum foil collars around the stems. Adult moths can be trapped using commercial traps baited with an attractant. One trap is adequate. You can spray the stem and root collar with Diazinon or Sevin in a water solution. Remember to remove all plant material in the fall after harvest and burn.
* The wireworm overwinters as an adult beetle. The eggs are laid in May and young larvae feed on the roots of corn, beets, carrots, lettuce, potatoes, radishes, turnips and cole crops. Adult beetles are known as click beetles. Treat the rows with Diazinon before planting or you can spray a Diazinon/water solution to the root collar area of your plant. Sanitation following harvest is the best preventative control.
* The red turnip beetle overwinters in the egg stage. Larvae hatch in June and feed on the roots of young turnips and adults feed on both the leaves and roots. You should spray the root collar area of the plant with Diazinon in a water solution. Other ways to fight the problem are to treat the root collar area with rotenone, wood ashes, diatomaceous earth, or old sawdust. Rosemary, sage, tansy or marigolds also act as an insect repellent.
* Slugs usually overwinter as eggs which hatch into larvae in the spring. They feed on most succulent plants. You should hand-pick slugs and destroy them in salt water. Another trick is to bait them with open cans of beer. Be sure and save a little beer for the gardener.
* Aphids overwinter in the egg stage; new adults emerge in May. Aphids such the plant fluids from the leaves and stems and weaken the plants. Black sooty mold sometimes grows on the sticky excess plant fluids found on the leaves. You can treat the plants with rotenone, wood-ashes or high volume spray of water to wash the aphids from the plants. Planting marigolds, chives, garlic or pennyroyal might be effective. You can spray such vegetables as beans, peas, turnips, lettuce, potatoes, pumpkins, squash, peppers, radishes and all with Malathion, Sevin or Diazinon in a water solution.
Be sure to control the temperature and humidity of your greenhouse. Be on the lookout for aphids on green peppers and eggplant. If you put an aluminum foil circle around the base of the aphid infected plant, the aphids may lose their orientation and disappear, it has been reported.
Many gardeners are concerned with the spear-marked black moth, a serious defoliator of birch trees. The moths seek only the moisture of the garden to fulfill their life cycle. Then they will deposit their eggs in the upper canopy of the birch trees in clusters on the upper surface of leaves or in the folds of leaves that have been rolled by leaf rollers.
The larvae feed on foliage of birch, alder, willow and rose. Direct control measures have not been recommended for this pest. Populations usually decline within two years. However, it wouldn't hurt to water and take care of your favorite trees during this insulting time.
Carpenter ants can be controlled with a 5 percent Diazinon solution added to a bait of sugar and cornmeal. Like all pesticides, read the label and keep out of the reach of children
In Fairbanks, Alaska we get about 15 inches or so of precipitation a year. This makes us somewhat of a desert!
When we get any rain, it is usually not enough to thoroughly wet our silty loess soil. It usually only dampens the top layer of the soil.
In order to grow decent plants in the Sub-arctic, you have to give them good soil, water, food and sunlight, and you need to beat back the weeds.
You should water your garden deeply enough so that the soil under the plant roots is wet. Water plants deeply and less often. Remember that the soil beneath the surface will not evaporate as quickly as the crusty top layer.
Try to make a little reservoir or basin around each plant. Take the nozzle off your hose and water into the reservoir, as you walk down your garden row. Come back and do it again a couple of times to saturate your soil. IT is better to give the plants a good saturation with our cold well waters on a single warm day, rather than a series of light blasts with the nozzle daily.
In watering an established lawn, flood the area until puddles form. By doing it a second time, you can insure that the soil is deeply watered. This will make your lawn survive during the frequent dry spells.
If you're establishing a new lawn you should keep the little grass seedlings moist at all times by using the finest spray on your nozzle. When the grass matures, switch to a sprinkling system.
One of my old friends from long ago, Jeff Studdert, was a dog-musher and also a wonderful gardener. He had a beautiful greenhouse and a lovely yard and garden. Jeff and his wife Maisie always warmed their water in large drums before they put it on the plants in the greenhouse. Tomatoes, cucumbers and spaghetti squash thrived on the kind attention.
Jeff also made a "manure-tea," putting steer or horse manure into a weighted onion sack at the bottom of one of his drums of water. It worked fantastic wonders on his plants. Life-long friends, Pat and Gene Rogge used to do the same thing.
Eloise DeWitt pampers the vegetables she thinks crave warm feet, such as corn, squash, cucumbers, tomatoes and beans. "No plant likes to go thirsty, let alone dry, which is highly damaging to tiny, delicate roots," she says. "The one sure way to grow inferior vegetables is to let them go dry."
In order to keep the weeds down and to keep moisture in the soil, use a mulch. By doing this your vegetables and flowers will be outstanding, since they won't have to compete with the horrible weeds like lambsquarters, shepherd's purse or chickweed.
You can use black plastic as weed control mulch. Hay, straw, leaves, grass clippings, compost, carpeting, newspapers or horse manure with wood shavings also will do the trick. I have found that one of the greatest ground covers is Tevlar, a porous plastic material that lets water through. I have covered my perennial bed with it. Putting rocks and cedar chips on top. Looks great. Eloise Dewitt said, "The time and energy spent in spreading mulch is minimal compared to that spent weeding and watering."
Start mulching in mid-June. This is after our soil has had a chance to warm up a bit. If you mulch too soon, the growth of your plants will be stunted. Three or four inches of mulch is about right when using organic materials. Anything greater than that will keep the ground too cold. Use organic materials in this way and you will smother the weeds, conserve moisture, decompose the material for future soil fertility, add humus and provide a feast for earthworms, according to Eloise.
DeWitt's favorite mulching material is old straw hay, which can be purchased cheaply at feed stores. This material is no longer good for animal consumption and therefore the price is lower. Before you put the mulch on, soak the ground thoroughly. You might have to wait a day or two before you can walk in the super-saturated garden to apply the mulch. Have patience. You will be rewarded later on. Eloise has a garden 25 by 75 feet. She uses from eight to 10 bales of hay.
Clear plastic hastens soil warm-up and keeps the moisture in the soil. Under plastic weeds grow luxuriously. Dachthal is a good pre-emergent to put on your soil right after rototilling to try and keep the weed seeds from germinating and growing so luxuriously. You have to use clear plastic mulch in sub-arctic Fairbanks, Alaska to grow corn, squash, string beans, peppers, tomatoes and cucumbers outdoors, however.
Ginger Gauss of Ladyslipper Gardening Consultant mentions the use of the drip method irrigation. This a method of watering using small holes in a hose where the plant is. It is good for use under clear plastic mulch. According to Gauss, the small holes allow only a little water to go through the opening. The trickle theory supposes each plant gets just enough water and the spaced holes water only the "good" plants. Water isn't wasted on weeds, unless they are within the vegetable water circle!
It was a happy time when, after 40 years, I re-met Clyde Lawson, a pioneer of Fairbanks, Alaska. He said the last time he saw me was when I was being wheeled around by my mother in a baby buggy!
Here in Fairbanks, Clyde and his dear wife, Edna, toured me through their beautiful garden on lower Fourth Avenue. They have been gardening in the same spot since before my time.
I was curious to know about his garden magic, especially in his success for growing carrots. He told me that the soil in his greenhouse and garden is about the same. He uses about 1/3 sand, 1/3 peat and 1/3 steer manure.
Already his perennial flower garden is blooming with trollius, lilies, columbine, Jacob's ladder and iris. His peony bushes are about ready to burst into bloom. His annual flower beds are filled with dahlias and special plants that came from seed given to him by someone who attended an annual Amsterdam flower show this past winter.
Clyde says that his carrot patch does very well in a light, rich and deep sandy soil. Heavy, wet or stony soils cause misshapen carrots and give poor yields. If the carrot's root reaches hard soil before it has grown to its proper length it will branch out and be undesirable.
Clyde has put many loads of steer manure from the old Bentley and Creamer's dairies, local stables and chicken farms in the sandy loam. His soil is very light and tillable. Clyde waters deeply to provide a good supply of moisture to the carrot root. The garden should be plowed to a depth of 10 inches and garden fertilizer should be added at this time. A second application in mid-summer helps the crop along. Stable manure can be applied to the garden at the time of rototilling. Rotted or old manure contain fewer weed seeds to occupy the land before the carrot seeds have germinated.
Among the recommended kinds of carrots for the Fairbanks area are: Scarlet Nantes, Spartan Bonus, Early Cross and Royal Chantenay.
Clyde says to exercise every precaution against weeds. Pick them. Chickweed must be killed early or the slow germinating carrots will be smothered.
The University of Alaska Cooperative Extension Office Master Gardening Class also suggests using Lorox or Linuron, a pre- or post- emergent weed killer that works well on annual grasses and broadleaf weeds. It can be applied as 11/2 pounds active ingredients per acre in 20 gallons of water. Be sure to use wetable powder precautions when dealing with herbicides.
Sow the carrot seed in rows as early in the spring as the ground is in good condition. The seed should be covered about 1/2 inch. In some cases the seed is placed in damp sand and allowed to swell and almost germinate before being sown, but Clyde doesn't use this practice. Many people put a little turnip seed with the carrot seed to mark the rows; the turnip seeds will sprout more quickly than the carrot seed. The rows should be planted about 18 inches apart.
Carrots should be thinned when they are 1 to 3 inches high. Be sure to leave enough carrot plants for a good crop. Some people thin twice. The first time thinning could be 11/2 inches apart. This will give you an abundance of finger-sized carrots. The carrots should be thinned the second time to stand about two or three inches apart. This gives the carrot plenty of room to grow and mature.
Be sure and harvest before the "hard" frost in September.
Carrots can be conveniently dug with a potato digger. This loosens the soil to make the carrots slide out easily from the ground.
Rosemary and sage are herbs that work well as companion planting to control any insects that might attack carrots.
Hope your carrots grow long and sweet!
At 18.5 Mile Chena Hot Springs Road is a two-acre, well-attended garden area that is part of Bob Hirn's Two Rivers Truck Farm..
As I was driving into the Hirn homestead, carrot tops more than a foot high caught my eye. Hirn, who has been in Fairbanks since 1949 and a homesteader since 1959, has a great way of raising carrots using solar heat. They are ready for the table by the end of June.
His method is to raise the carrot patch at a very reachable and workable level. The plan is similar to having greenhouse benches with a small portable greenhouse top that's used in early April--until weather permits its removal.
In an ingenious way Bob has used six 55-gallon drums, which are laid on their sides, and filled with water up to the bung hole. He screws the cap on and has six potential solar heaters at his disposal. He maintains that there is enough air space above the bung hole to allow for water expansion in the depth of our sub-arctic winters.
His carrot patch is grown in galvanized metal beds with drainage holes. The beds are 4 feet by 24 feet and 14 inches deep. He uses twin-walled Chapin irrigation hoses, which sprinkles water out at intervals.
Into his beds he puts two-fifths sand, two-fifths manure and one-fifth dirt, with five pounds of bone meal.
Initially, Bob uses a pelleted fertilizer. Then, periodically, he applies a water soluble fertilizer such as 10-52-17 through his irrigation hoses.
The framing for the carrot patch is made of two-by-fours to a dimension of 4 feet high, 24 feet long and 4 feet wide. A heavy-duty polyethylene film is secured around the sides of the structure to keep in the solar heat. The greenhouse top is made of corrugated clear film that can be easily lifted by two people.
By using this solar heating method, Bob starts his carrot patch when the snow is still on the ground in early April. The water in the barrels thaws the beds early--much earlier than the type of raised beds that sit on the ground. He grows Emperator 408, Scarlet Nantes, Emperator Special 58 and Spartan Bonus in his patch.
Since chickweed is a problem for commercial carrot growers, Bob uses a cleaning Stoddard solution when his carrots are one or two inches high. He says it seems to knock his chickweed problem. Of course, you can opt to pull the chickweed by hand or follow the directions in the University of Alaska Cooperative Extension Service pamphlet number P-140 called Weed Control in Cabbage, Carrots, Lettuce and Peas.
The carrot beds are approximately at waist level, which eliminates bending. The width is comfortable so that you can reach the middle from either side. For an individual patch, the bed could be a lot shorter. Still, the volume of carrots produced would be enough for you, your neighbors and the neighbor's horse.
By using aged manure the moisture-holding ability of the soil is improved. The requirement for sunlight remains the same as for any other outdoor garden. Soil drainage can be regulated by the recommended soil composition that Bob suggests. Be sure to put drainage holes in your bench.
If you decide to use wood for your bench, even though Bob doesn't recommend it, instead of corrugated metal, be sure the wood is going to be able to withstand the constant moisture. You can line the wood with polyethylene sheeting and only allow for drainage. Or, you can use a preservative for the wood. But, do not use creosote or Penta. These chemicals will save your wood but can kill your plants. Copper naphthenate is the only wood preservative to use on wood which comes in contact with plants!
Building and preparing your waist-high solar garden may require some expense and effort. But, it can greatly increase your carrot-growing possibilities.