Frequently Asked Questions

Question:
Are there any peach varieties that can be successfully grown in Iowa?
Answer:

Peaches are not reliably cold hardy in most parts of Iowa.  It is possible to grow ‘Reliance’ (yellow flesh, freestone) and ‘Polly’ (white flesh, clingstone) in the southern one-third of Iowa. 

Growing peaches in Iowa is...

Question:
Can hollies be successfully grown in Iowa?
Answer:

American holly (Ilex opaca) and English holly (Ilex aquifolium) are prized for their glossy, green leaves and brightly colored fruit. Sprigs of both hollies are often used in wreaths, centerpieces, and other Christmas...

Question:
There are yellow-green bugs eating the flowers on my roses. What are they and how can they be controlled?
Answer:

The yellow-green bugs are probably the adults of the northern corn rootworm.  The larvae of the northern corn rootworm feed on the roots of corn plants.  The adults (yellow-green beetles) appear in mid-summer and are present until frost...

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:
When and how do you divide bearded irises?
Answer:

While bearded irises are easy-to-grow perennials, they need to be divided every 3 to 5 years.  If not divided, plants become overcrowded and flower production decreases.  Crowded plants are also more prone to disease problems.  In...

Question:
When should I harvest rutabagas?
Answer:

Harvest roots when 3 to 5 inches in diameter.  The foliage may also be harvested for greens.  Prior to storage, trim off the foliage to within 1 inch of the crown with a sharp knife.  Also remove the tap root.  Rutabagas...

Question:
Which perennials can be divided in late summer?
Answer:

The best time to divide perennials varies with the different plant species. While most perennials are best divided in early spring, late summer/early fall (September in Iowa) is a good time to dig and divide peony, daylily, garden phlox, hosta,...

Question:
Is a tomato a fruit or a vegetable?
Answer:

There are different ways to classify or categorize plants and plant structures.  Botanically, the typical plant has roots, stems, leaves, flowers, and fruit.  The root is the edible portion of carrots, radishes, beets, and parsnips....

Question:
How do I have my garden soil tested?
Answer:

Soil testing services are provided by neighboring universities and private laboratories.  Information on how to collect good soil samples for testing and recommendations for how to find testing laboratories can be found at ...

Question:
When should I harvest my bell peppers?
Answer:

Bell peppers are usually harvested when large, firm, and dark green (immature stage).  They may also be allowed to fully ripen to red, yellow, orange, or other colors.  Fully mature bell peppers are slightly sweeter and contain higher...

Question:
Can blueberries be successfully grown in Iowa?
Answer:

Blueberries can be successfully grown in Iowa.  However, they do have special growing requirements. 

Blueberry plants require a sunny location and a well-drained soil high in organic matter.  Avoid wet, poorly drained sites...

Question:
My 'Sunburst' honey locust is not growing well. What could be the problem?
Answer:

The ‘Sunburst’ honeylocust has distinctive yellow-green foliage.  Unfortunately, it is not a vigorous tree.  It grows slowly and is susceptible to cankers and mimosa webworms.

Cankers, caused by fungal pathogens, are localized...

Question:
Should I remove the grass clippings when mowing the lawn?
Answer:

When the lawn is mowed properly, grass clippings do not need to be removed or bagged.  Small clippings filter down into the turf and quickly decompose, returning essential plant nutrients to the soil.  Lawn clippings do not...

Question:
What causes my peaches to rot and turn brown?
Answer:

Brown rot is a common fungal disease of peaches and other stone fruits.  Affected fruits develop circular light brown spots that expand rapidly and rot the fruit.  Sometimes the fungus that causes this rot is visible as ash-gray tufts....

Question:
There is a large, hard growth on the cane of one of my roses. What is it?
Answer:

The large, hard growth is probably crown gall.  Crown gall is caused by the bacterium Agrobacterium tumefaciens.  The bacterial disease can infect roses, grapes, apples, raspberries, willows, euonymus, and many other woody...

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:
How can I control the iris borer?
Answer:

The iris borer is a serious pest of bearded irises.  The mature stage of the iris borer is a grayish moth.  Female moths lay eggs on iris foliage and other nearby plants in late summer/early fall.  The eggs hatch the following...

Question:
When can radishes be planted in Iowa?
Answer:

Radishes can be planted as soon as the ground can worked properly in spring.  This is often late March in southern Iowa and mid-April in northern counties.  Successive plantings can be made every 7 to 10 days through May.  Radish...

Question:
A yellow, foam-like growth has suddenly appeared in my mulched perennial bed. What is it and will it harm my plants?
Answer:

The growth in your perennial bed is probably a slime mold. Slime molds are types of fungi. Slime molds feed on bacteria and other organisms in the mulch. They do not harm plants.

Slime molds are usually a temporary nuisance. Within a few...

Question:
Several leaves on my tomato plant have curled up. Why?
Answer:

The curling of the tomato leaves may be a physiological disorder referred to as leaf roll.  Affected leaves roll upward and inward.  The leaves may also become thickened, giving the foliage a leathery appearance. 

Leaf roll...

Question:
When would be a good time to move an evergreen tree with a tree spade?
Answer:

Early spring (before bud break) is the best time to transplant evergreens.  Evergreens can also be transplanted in late summer (late August to mid-September).  Evergreens transplanted after mid-September may not have adequate time to...

Question:
How can I dry hot peppers?
Answer:

Drying peppers is a simple procedure.  Harvest mature peppers (the fruit of most varieties turn from green to red at maturity), wash to remove any dirt, then allow the fruit to dry for a few minutes on the kitchen counter.  Once the...

Question:
How do I stop birds from eating my blueberries?
Answer:

Birds are the biggest threat to the blueberry crop in the home garden.  If not controlled, hungry birds may devour most of the crop.  Scare devices are sometimes helpful.  However, netting is the most effective way to protect the...

Question:
I just planted some blueberries. When can I expect them to produce a crop?
Answer:

Blueberry plants should not be allowed to bear fruit in the first 2 years.  Any blossoms which form should be removed (rubbed off).  Removal of the flowers will maximize vegetative growth and increase yields in later years. ...

Question:
How do I get rid of moles in my yard?
Answer:

Trapping is the best way to get rid of moles.  Trapping isn't easy, but it does work.  Patience and persistence are required.  Traps can usually be found in hardware stores and garden centers.  When using traps, carefully...

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