Frequently Asked Questions

Question:
What causes pine wilt?
Answer:

Pine wilt is a common disease that causes browning and death of pines, especially Scotch pine. Austrian, mugo, red, jack, and white pine may also be affected, but less commonly than Scotch pine. Affected trees turn brown and die within a few...

Question:
How often should I water my lawn?
Answer:

Most lawns in Iowa require 1 to 1½ inches of water per week.  When watering the lawn, apply this amount in a single application or possibly 2 applications 3 or 4 days apart.  Avoid frequent, light applications of water which promote...

Question:
Do blueberries have insect and disease problems?
Answer:

Phytophthora root rot can be a serious problem in poorly drained sites.  Phytophthora root rot can be avoided by planting blueberries in well-drained soils.  Outside of root rots, blueberries generally have few insect and disease...

Question:
My sycamore is losing some of its bark. Is there something wrong with the tree?
Answer:

Shedding bark on some trees is a completely normal development. The bark of most young trees is smooth and thin. As the tree grows, the bark layer thickens with the outermost tissue eventually dying. Continued growth pushes the bark outward,...

Question:
As the snow melted over the last few weeks, several narrow meandering pathways appeared in my lawn. What produced them? Will the grass recover?
Answer:

The runways in the lawn were likely caused by the meadow vole.  The meadow vole is a small, brown, mouse-like animal.  Though common in Iowa, the meadow vole is secretive and seldom seen by most individuals. 

Voles are...

Question:
Should I water my raspberries during dry weather?
Answer:

Watering raspberry plants during dry weather can help insure a good crop.  Adequate soil moisture levels are necessary throughout the growing season for good raspberry production.  However, the most critical time for moisture is from...

Question:
How often should I water bee balms?
Answer:

Bee balms like an even supply of moisture during the growing season.  For best performance, water bee balms every 7 to 10 days during dry periods.  When watering, soak the soil to a depth of 6 to 8 inches.  Apply a mulch around...

Question:
How do I prevent straw from blowing off my strawberry bed in winter?
Answer:

In windy, exposed areas, straw mulches can be kept in place by placing wire or plastic fencing over the area.  The fencing can be held in place with bricks or other heavy objects.

Question:
I would like to establish some perennial beds in my yard, but I don't have a great deal of time for maintenance chores. What are some good low maintenance perennials?
Answer:

All perennials require some maintenance.  Watering, fertilizing, pinching, staking, deadheading, dividing, and providing winter protection are common maintenance chores.  Some perennials require frequent attention through the growing...

Question:
Why are my potatoes knobby?
Answer:

Fluctuations in soil moisture levels during tuber development may cause knobby potatoes.  Watering on a regular basis (about once a week) during dry periods will help prevent this problem.

Question:
How long should I continue to water a newly planted tree?
Answer:

The roots of trees continue to grow until the ground freezes.  If the weather is dry, continue to water newly planted trees until the soil freezes in winter.  Small trees usually require watering for 1 or 2 growing seasons.  It may...

Question:
A blackish spot develops on the bottom of my tomato fruit. What is the problem and how can it be prevented?
Answer:

Blossom end rot is probably responsible for the blackish spots on the tomato fruit.  Blossom end rot is a common problem on tomatoes.  It appears as a brownish black spot on the blossom end (bottom) of the fruit.  Secondary...

Question:
How can I determine if my oak tree has oak wilt?
Answer:

Oak wilt is a serious disease that can infect many oak species.  It is caused by the fungus B. fagacearum.  Red and pin oaks are very susceptible to the oak wilt fungus and can die within 4 to 6 weeks.  White and bur oaks...

Question:
How often should I aerate a lawn?
Answer:

The frequency of aeration is largely determined by the soil type and the amount of use.  Lawns growing in heavy, clay soils and those subject to heavy foot or pet traffic should be aerated twice a year.  Once a year should be sufficient...

Question:
When should I harvest sour cherries?
Answer:

Sour or pie cherries should be harvested when the fruit are full-flavored, somewhat soft, and juicy.  (Cherries picked before they are mature will not ripen off the tree.)  For immediate use, the cherries can be picked without the stems...

Question:
There are several bands of holes around the trunk of my pine tree. Is the tree infested with borers?
Answer:

The holes were likely created by sapsuckers.  Sapsuckers, members of the woodpecker family, damage trees by drilling holes in the trunk or large branches.  Sapsucker damage is very distinctive.  They drill uniform, 1/4 inch holes...

Question:
What is the proper way to deadhead roses?
Answer:

Deadheading or the removal of faded flowers is done to encourage additional bloom on hybrid tea and other repeat-flowering roses.  Hybrid tea roses usually have one or two 3-leaflet leaves immediately below the flower.  Next (lower down...

Question:
We recently moved into a home that has a large red raspberry planting in the backyard. How should we rejuvenate the planting?
Answer:

Red raspberries sucker freely.  If not confined, plants will spread rapidly.  Red raspberries are most productive when grown in 2-foot-wide hedgerows.  If the raspberry planting is several feet wide, plant rows need to be...

Question:
My chrysanthemums get tall and lanky and flop over onto the ground in fall. What can be done to prevent this?
Answer:

Pinch newly planted and established mums from spring to mid-summer.  Remove the upper 1 to 2 inches of the shoots when the stems are 6 to 8 inches tall.  New lateral (side) shoots will develop along the stems.  Pinch again when the...

Question:
Do I need to treat my peas with an inoculant before planting?
Answer:

Peas are members of the legume (Fabaceae) family.  Through a symbiotic relationship with a soil bacterium (Rhizobium), peas are able to “fix” atmospheric nitrogen in nodules on their roots. 

Peas will grow and produce a crop...

Question:
What are some good, long-lived perennials?
Answer:

When selecting perennials for the home landscape, it’s important to consider their size, bloom period, hardiness, and cultural requirements.  Another consideration is their longevity.  Some perennials are short-lived.  Short-lived...

Question:
Are rhubarb leaves safe to put in the compost pile?
Answer:

While rhubarb leaves do contain poisonous oxalic acid, they can be placed in the compost pile.  Oxalic acid, like other organic acids, are not readily absorbed by plant roots.  Compost containing decomposed rhubarb leaves can be safely...

Question:
I need to have some tree work done. How do I select a qualified arborist?
Answer:

Trees are valuable assets to the home landscape.  Occasionally the services of a professional arborist are needed to prune a large tree or assess the condition of a tree after a storm.  For many individuals, selecting an arborist is a...

Question:
What can I use as a mulch around my tomato plants?
Answer:

Several organic materials can be used as a mulch around tomato plants.  Suitable mulching materials include:

  • Dry grass clippings (Do not collect grass clippings from lawns that have been treated with a broadleaf herbicide...
Question:
Several new shoots on my crabapple have turned brown and wilted. What is the problem?
Answer:

Fire blight is probably responsible for the wilted shoots on your crabapple.  Fire blight is caused by  the bacterium Erwinia amylovora.  Plants susceptible to fire blight include apple, crabapple, pear, hawthorn, and...

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