Skip to main content

Hort Update for November 14, 2017

Nebraska Extension Hort Update for November 13, 2017
Prepare now for next season's orchard spray program.
LawnsMajor Symptom:
1. Dormant seeding Do soil prep now; seed after Thanksgiving or early March
2. Limit traffic on frozen turf Frozen blades are damaged by foot or vehicle traffic
3. Late season watering Too much, then too little; winter watering needed?
Trees & ShrubsMajor Symptom:
4. Late season planting & winter care Complete before soil freezes; extra care needed
5. Buy a local holiday tree Nebraska Christmas Tree Growers list
Landscape OrnamentalsMajor Symptom:
6. Rose mulching & winterization Mulch, prune if needed after plants are dormant; best to prune in spring
Fruits & VegetablesMajor Symptom:
7. Asparagus - to cut back or not? Allowing stems to stand over winter provides some benefits
8. Prepare next season's spray program Develop a spray program tailored for the pests in a home orchard
MiscellaneousMajor Symptom:
9. Pesticide storage Read and follow label directions for safe storage conditions
10. Care of holiday plants Needed when transporting plants as well as in the home
11. Controlling mice Effective control involves sanitation, exclusion and population control

1. Dormant seedingDo soil prep now; seed after thanksgiving or early march

The best time to seed cool season turfgrass is late August/early September. Two other seeding times are spring and dormant seeding. Dormant seeding is defined as such because seed lies dormant until soil temperatures warm in April or May. Dormant seeding can be done as early as Thanksgiving or as late as March in most locations. The key is to seed after the soil is cold enough that germination will not occur until after soils warm in spring. The benefit of dormant seeding is as soil heaves and cracks during winter, crevices are created for seed to fall into, providing ideal germination conditions in spring. Dormant-seeding may be easier to schedule than spring seeding, because spring rains can make it difficult to seed after March.

There are risks with dormant seeding. It is most effective if weather remains cold enough to delay germination until spring. Occasionally, extended warm periods in winter could allow seed to germinate, and seedlings may then be killed by ensuing cold weather. As with any seeding, soil preparation needs to be done prior to seeding. For dormant seeding, this would be in fall before the soil freezes. If using dormant seeding, monitor the area in mid spring for the need to do additional over-seeding.

Establishing Lawns from Seed, Nebraska Extesion Turf iNfo


2. Limit traffic on frozen turffrozen blades are damaged by foot or vehicle traffic

It is best to minimize winter traffic on any turf area and especially when frost is present on green turf. If ice crystals (frost) have formed and foot or vehicle traffic occurs, the physical abrasion can damage turfgrass. Winter traffic can cause cosmetic damage, physical abrasion, and/or soil damage depending on the situation. Too much traffic on turfgrass at a time when it cannot recover also leads to winter injury. Winter golf or over-using soccer fields during winter are examples.

Winter Turf DamageNebraska Extenion Turf iNfo


3. Late season wateringtoo much, then too little; winter watering needed?

All the moisture we had in October may not have been all that good for turfgrass. Light drought stress prior to winter can help turf harden off before severe cold. On the other hand, visible drought going into winter may place turfgrass at greater risk of winter dessication injury. The wet conditions in early October didn’t allow for much drought/cold preconditioning. Since then, there has been a lack of rainfall and warm October weather lead to a fair amount of drying. This is the time of year we begin to hear questions about the need to “winter water”. Turf that received some irrigation or rain up until November is likely fine, depending on soil type. However, ensuing winter conditions will determine potential for injury. Timely rain or snowfall may be all that is needed. If we have an open, dry winter, some injury might occur.  


4. Late season planting & winter careComplete before soil freezes; extra care needed

Fall is a good time to plant trees and shrubs. The months of September and October are best to allow new root growth for a longer period of time. However, deciduous trees and shrubs can be planted up until the soil freezes. Know that if fall planting extends into November and December, or slow to establish species are chosen, root growth may be poor and planting failure could occur. If planting does take place after November 1, plant correctly and keep the root ball and surrounding soil moist up until the soil begins to freeze. Place a two to four inch layer of mulch around the tree to reduce moisture loss from soil. If we have an open, dry or warmer than average winter, check the soil around the new tree for needed irrigation.


5. Buy a local holiday treeNebraska Christmas Tree Growers List

With Christmas tree buying around the corner, encourage “buying local”. For clientel who want to cut their own, the Nebraska Department of Ag has a Nebraska Christmas Tree Growers Directory listing local tree farms across the state. 


6. Rose mulching & winterizationmulch, prune if needed after plants are dormant; best to prune in spring

Pruning is not needed during fall for shrub roses, such as Knock Out, Buck roses, or Nearly Wild.  They are very winter hardy and do not need special protection.  Prune in April, removing dead or damaged branches, and adjusting plant height.

However, hybrid tea, grandiflora, floribunda and some cultivars of miniature roses need winter protection.  These plants may need pruning to allow them to fit beneath a winter protection method, such as a rose cone, and to remove very tall laterals that may be damaged by winter winds. The majority of pruning should be done in April as new growth begins.

Most roses are protected by covering them. The key is to wait until the plant is hardened off and temperatures are cold. Do not put rose protection in place until soil has frozen or night temperatures are consistently dropping into the 20s at night. One good mulching method is the encircle the rose with a chicken wire cage staked to hold it in place, then fill the cage with coarse leaves. For best growth, wait until April and then prune to remove winter killed wood. Or mound 8 inches of soil around the base of roses after soil temperatures have cooled in late fall to protect the plant crown. Use a well-drained soil for this rather than one high in clay. After mounding, moisten the soil mound. After the soil is frozen, apply coarse mulch.


7. Asparagus - to cut back or notAllowing stems to stand over winter provides some benefits

Cutting back asparagus in fall is a common practice for many gardeners. But allowing asparagus stems to stand does provides some benefits to plants.

  • Standing asparagus fronds trap snow during winter, providing moisture for the crown as the snow melts.
  • Nutrients in the stems are transported into the plants' crown if stems are allowed to stand until later winter, February or March. By then the stems will be brown and all nutrients will have moved into the plant crown.
  • Allowing asparagus fronds to stand in late winter delays new stem emergence, which can be a useful technique where late freezes are common.

However, if you have an older female cultivar of asparagus, such as Mary or Martha Washington, asparagus seedlings can become a problem in the garden. In this case, cutting back stems in the fall and removing as much seed as possible from the garden minimizes asparagus weed problems next year.


8. Prepare next season's fruit tree spray programdevelop a spray program tailored for the pests in a home orchard 

Before the pest problems that affected your tree and small fruits this year have completely faded from memory, make a list and prepare a 2018 management plan. Catalogs have beautiful pictures of apples, pears, peaches and other fruits which are tempting to the home gardener. But growing unblemished fruits is difficult. Good home fruit management begins with monitoring plants for common pest problems and controlling those pests that occur. An integrated pest management (IPM) program can reduce the amount of pesticides needed, but some pesticides may still be needed. 

The specific pesticides needed and time of application depend on what pest problems appear in a home orchard. Do not spray for all pests, only those affecting your plants so pest diagnosis is a critical first step. Then use the publications below to develop a spray program tailored for your specific pests. 

Fruit Spray Schedules for the Homeowner, University of Missouri Extension
Midwest Fruit Pest Management Guide (commercial growers), Purdue University


9. Pesticide storageread and follow label directions for safe storage conditions

Store pesticides correctly and securely.  Storage information can be found on pesticide labels.  Read and follow it for safety and to help keep pesticides from degrading so they may no longer be as effective.

In general, pesticides need to be stored in a secure, well ventilated location that can be locked. The location should be away from children, pets and food items as well as anything that might be contaminated in case of a leak or accidental spill. 

Do not store pesticides near heat, sparks, or open flames; and check that containers are tightly closed. Always store pesticides in their original containers.  A mistake made is pouring a pesticide into a container other than the original. This is against pesticide label law and has led to accidental poisonings. 

A common question about winter storage is if a pesticide is still effective after it freezes.  Most pesticides are safely stored between 40 and 100 degrees Fahrenheit, but it is best to check the label for storage temperature requirements and any warnings against freezing.  If a liquid pesticide does freeze, it might be less effective in controlling pests. 

Pesticides contain active and inactive ingredients. The active ingredient is what kills the pest. Inactive ingredients include solvents, carriers, or emulsifiers that make the pesticide more efficient. Due to some inactive ingredients, the freezing point of some liquid pesticides could be lower than 32 degree F. Read the label for temperature storage requirements and what to do if a pesticide does freeze.          

Pesticides formulated as wettable powders or granules are not affected by low temperatures. However, moisture can cause caking that may reduce effectiveness so follow label directions for correct storage recommendations. If you have products formulated in water-soluble packets, these should not be frozen as they tend to become brittle and then break open.

Safe Transport, Storage, and Disposal of Pesticides, Nebraska Extension


10. Care of holiday plantsneeded when transporting plants as well as in the home

Care of holiday plants begins when the wholesale truck delivers the plants to the store and at the point of purchase. Avoid chilling injury when unloading the truck; and when transporting plants from the store home. Once unloaded off the truck and brought home, promptly remove the paper or plastic sleeve placed around the plant. If a plant sleeve remains around a plant for more than 24 hours, ethylene gas produced by the plant will cause leaves to begin dropping. Check the potting mix to be sure it is moist. Inspect plants closely for signs of insect pests; treat and quarantine any found to be infested. Display most plants where they receive fairly bright light and away from warm or cold air drafts. Soilless mixes dry out quickly in dry indoor air. Check plants daily for watering needs. When plants are purchased, they need to be wrapped in a plastic bag to protect them from chilling injury while transported from the store home. For information on specific plants, see link below.

Selection and Care of Holiday Plants, Iowa State University


11. Controlling miceEffective conrol involves sanitation, exclusion and population control

Exclusion is the best means of keeping mice from invading buildings. Mouse-proof construction is a key element in an effective mouse control program. Mice are attracted to buildings when they detect openings and escaping heat. Prevent mouse entry by eliminating all openings one-fourth inch or larger. Secure gaps less than one-half inch around pipes with sealant or mortar to stop airflow. For larger gaps, use copper woven-wire mesh or a new product that uses stainless steel fibers to fill the gap. These products do not rust and are flexible enough to be wedged into small cracks and crevices by a flat head screw driver. Complete the job with the appropriate type of sealant or mortar to prevent air movement. Larger openings can be secured with wood, aluminum flashing, concrete, or one-fourth inch wire mesh. Doors, windows, and screens should fit tightly. Cover the edges of doors and windows with metal to prevent gnawing. Latex, plastic, rubber, boards less than one-half inch thick, or other soft materials are unsuitable for plugging holes used by mice.

Rodent-Proof Construction, Nebraska Extension
Controlling House Mice, Nebraska Extension


Seasonal information for Nebraska's green industry professionals.

Continuing Issues


Trees & Shrubs

Landscape Ornamentals

Fruits & Vegetables

Local Conditions

Professional Associations

Industry Partners