Winter Garden Preparation - Soil

Ideal garden soil should be loose, deep and crumbly. It should drain well, water should not stand on top after rain and contain plenty of organic matter. Good garden soil will deliver the right mixture of air, water, and nutrients to grow a large root system and strong, productive plants. Vegetables and other plants will grow satisfactorily with a wide range of soil types from sand to clay if certain steps are followed for overcoming their basic short-comings.

Begin preparing the soil by removing all plant material from this year's garden. Dead roots, stems and foliage can harbor insects and diseases that emerge in the spring to infect next year's garden.

Soil testing can provide important information to make decisions concerning:

• How much lime to use in lawns, vegetable or flower beds.
• How much fertilizer to use on lawns, vegetables, flowers, and shrubs.
• How to adjust the soil pH for optimum growth of acid-loving plants such as azaleas and rhododendrons.
• How to apply soil amendments and fertilizer to improve soil quality.
• Nutrients that are lacking or in excess in the soil.
• Amount of lead or other metals in the soil.

Clay soils have the ability to hold moisture well and usually contain more nutrients than light soils. They dry slowly in the spring so early planting of crops is not possible. Water penetration is slow so irrigation water often runs off instead of entering the root zone. 

Sandy soils are easy to work but have low water holding capacities, so plants may suffer from moisture stress in hot weather. Nutrients may be lost as irrigation water moves downward through the soil. 

These almost opposite drawbacks of both soil types can be corrected by the same technique-adding organic matter. Fine clay particles can be physically separated by coarse organic material. Nutrient and water holding qualities of sandy soils can be increased. As the organic matter breaks down, its components continue to have soil improving characteristics. 

Begin by incorporating 2 to 3 inches of organic matter 6 to 8 inches deep. This application will not last forever and you should plan to add about 2 more inches each year. With heavy soils, you’ll need 2 or 3 years to see much of an improvement. Summer mulching or compost addition will be helpful.
 
When the soil has dried and warmed sufficiently, spade or rototill to a depth of about 6–8 inches. Garden soil doesn’t need to be “flour-fine.” Leave marble-sized particles and crusting will not be as severe as with over prepared soil. You’ll need to use a rake to pulverize clods. Level and compact the soil for a firm seedbed. The final soil surface should be as level as possible for uniform water penetration. 

Additional Resources

Rutgers Univeristy - How to Have your Soil Tested 

University of Minnesota - Organic Matter Management

Utah State University - Preparing Garden Soil

University of Maryland - Prepare Your Soil 

Alabama A&M and Auburn Universities - Raised Bed Gardening 

Some Winter Garden Chores

Snow and ice on trees and shrubs 

In winter, the threat of damage from snow and ice is always near. When snow piles up on evergreens, try to gently brush it off. Don’t shake the branches as this may cause them to break. If the snow is frozen on the branch and will not brush off easily, it is best to let it melt naturally, to avoid damage to the tree or shrub.

If tree limbs break due to the weight of ice or snow, it is advisable to have the broken limbs removed as soon as the weather permits. Hanging branches can be a danger to passing pedestrians. Also, the tree will be able to heal the wound better in spring if the wound has clean edges instead of ragged tears.

Seed orders 

If you order seeds from a catalog, get your order in by the end of January. Early orders help insure that you get the seeds you want and that you have them in time to start them indoors if you want.

Warm spells in winter 

Sometimes in the middle of winter, there are suddenly a few warm days. For the most part, this is not a big problem, but you may need to check on a couple of things. If you covered your roses with rose cones, you may need to ventilate the cone to prevent heat from building up inside. The same should be done with coldframes. If it is a warm, sunny day, the temperatures may be rising in the cold frame more than you expect. Remember to close vents as the temperature drops again at night.

Prepare Garden Equipment for  Spring

Avoid the spring rush by having your lawn mower and other gardening equipment serviced or repaired now. Winter is also a great time to clean, sharpen and organize your garden tools.

Winter Garden Cleanup

Winter is a good time to do some light garden cleanup. Remove dead plant material from the garden beds and pick up leaves that are left over from fall. Toss them into your compost bin, or use them to mulch around perennials.

Insects in Winter - Part One

Insect are cold-blooded animals and respond to cooling temperatures in a variety of ways. Mammals can generate their own heat and have the advantage of being large. Insects are small and do not have body fat for insulation from the cold and do not produce their own heat. However, they do have several general strategies which they can employ such as or dealing with winter.  One of the most interesting means that insects use to survive winters is physiologic.

Diapause

Diapause is a suspension of development that can occur at the embryonic, larval, pupal, or adult stage, depending on the insect species. In some species, diapause is optional and occurs only when induced by environmental conditions; in other species the diapause period has become an obligatory part of the life cycle.

Some species of insects over winter in the adult stage and avoid freezing damage to their body by making a sort of biologic antifreeze material. These insects synthesize compounds such as sugars and proteins which depress the freezing point. These chemicals are called cryoprotectants, such as glycerol - similar to the stuff we pour down our sinks to prevent freezing! As temperatures increase, cryoprotectants quickly decrease. Some insects, like many plants, undergo a cold-hardening when shorter days and cooler temperatures occur. The mechanisms providing over winter cold- hardiness results from a combination of supercooling and the insect- manufactured cryoprotectants. Some Alaskan insects can survie temperature as low as  -76 degrees F.


References

Danilevskii, A. S. 1965. Photoperiodism and Seasonal Development of Insects. Oliver and Boyd, Edinburgh. 

Nijhout, H. F. 1994. Insect Hormones. Princeton University Press, Princeton. 

Tauber, M. J., Tauber, C. A., and Masaki, S. 1986. Seasonal Adaptations of Insects. Oxford University Press, Oxford. 

Web Links

Developmental Biology

Insect Winter Survival Strategies

Insect Overwintering

Fall Weeds

Fall is the best time to control dandelions and other perennial weeds, such as ground ivy. In fall, the plant begins moving nutrients to the roots for storage instead of to upper plant parts for continued growth. If herbicides are applied at this time, the chemicals are transported to the roots along with the nutrients, killing the entire plant instead of just the parts above the soil surface.

The best control measures to use depends largely on correctly identifying the weed present, but one of the keys to controlling weeds effectively is making herbicide applications at the right time of year and for many broadleaf, perennial weeds like violets, ground ivy, and dandelions fall is an excellent time to get them under control.  Fall control of annual weeds like crabgrass, foxtail, etc. is not necessary. These weeds will die during the winter and do not germinate from seed until spring, making fall control unneccesary.

Many winter annual weeds, like field pennycress, shepherdspurse, chickweed and henbit, should also be targeted for controlled in the fall. Winter annual weeds germinate in fall, grow into a small rosette then overwinter and resume growth in early spring. A fall broadleaf pre-emergent application, such as Preen (trifluralin), Surflan, Pendimethalin or Dimension, should be applied in the fall to prevent weed seed germination, just as it does in the spring.

Before applying any herbicide, always have the weeds identified and follow the manufacturer's directions.  Use caution when applying herbicides around landscape beds since accidental spraying or spray drift can damage shrubs and ornamental plants.

Additional Information

New Jersey Weed Gallery - Rutger University

Henbit Information - UC Davis

Shepard's Purse - University of Illinois

Pennycress - Virginia Tech

Ground Ivy - Virginia Tech

Borax on Ground Ivy: Boon or Bane? - Iowa State University

Harvest of Trial Crops at Burlington County Ag Center

A sure sign that fall has arrived was the recent harvest of crops from the Burlington County Agricultural Center.  The crops were planted as a field trial for Rutgers University and are grown in research plots that are evaluated for their growth characteristics.  To find out what's in season throughout New Jersey this fall, visit either the Rutgers Jersey Fresh Information Exchange page or the NJ Department of Agriculture - Jersey Fresh page.

White Grubs

Recently, while walking in the neighborhood, I came across a number of white grubs crawling on a drive way.  While it may be a little too late to treat for grubs this fall, we thought it would be interesting to post this short video and some general information about white grubs.

White grubs (Order Coleoptera, Family Scarabaeidae) are 1/2 to 1-1/2 inches long, have three pairs of legs near the head, and characteristically rest in a C-shaped position. Their heads and rear ends are brown. Green June beetle grubs crawl on their backs with their legs up. Grubs can be identified by the pattern of spines (rasters) on the rear ends. It is important to know the kind of grub in order to know when to treat.

Generally, the procedure for treating for white grubs is:

• Determine the extent of your grub infestation


• Identify the Grub Species


• Select a Control Method


• Treat in the Fall

Not all lawns have grub infestations that warrant control. Lawns differ in susceptibility to white grubs because of differences in grass species, soil health, irrigation, amount of sun or shade, traffic, etc. A dense stand of grass with a healthy root system can generally tolerate up to 10 grubs per square foot.   Please read the resource cited below to obtain additional information on how to control white grubs.

Additional Information

Insect Management in Turf Grass: White Grubs

White Grub Identification