Frequently Asked Questions

Question:
How should I prepare my perennial beds for winter?
Answer:

Perennial plants can be cut back in fall after the foliage has been destroyed by a hard freeze.  Compost the plant debris. While this work can be done, it is not necessary to clear cut the perennial garden after the first freeze of the...

Question:
How do you store garlic?
Answer:

After harvesting the garlic, dry the garlic in a warm, dry, well-ventilated location.  Place the garlic on an elevated wire screen or slotted tray to promote drying.  When the tops have dried, cut off the dry foliage 1 inch above the...

Question:
What would be a good planting site for gooseberries and currants?
Answer:

Gooseberries and currants prefer cool, moist, well-drained sites.  Avoid poorly drained, wet soils and hot, dry sites.  To discourage fungal diseases, such as powdery mildew, select sites with good air movement.  Gooseberries and...

Question:
I recently received a flowering mum from a florist. Can I plant it outdoors?
Answer:

Florist or greenhouse mums are sold throughout the year at floral shops, supermarkets, and other retailers.  Unfortunately, florist mums do not perform well when planted outdoors.  Most florist mums will not survive the winter when...

Question:
When mowing the lawn, what is the proper mowing height?
Answer:

Kentucky bluegrass lawns should be mowed at a height of 2½ to 3 inches in the spring and fall months.  Mow bluegrass lawns at a height of 3 to 3½ inches in June, July, and August.  A higher mowing height in summer helps to cool the...

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

Kentucky bluegrass lawns should be mowed at the height of 2½ to 3 inches in spring and fall.  Set the mower blade to a height of 3 to 3½ inches during summer. 

As a general rule, never remove more than 1/3 of the total leaf...

Question:
I have some small, purplish spots on the canes of my black raspberries. What is it and how can it be controlled?
Answer:

The small, purplish spots are most likely due to anthracnose.  Anthracnose is a serious fungal disease of raspberries, especially black raspberries.  The disease is readily recognized by the small, purplish spots that develop on young...

Question:
Should I stake a newly planted tree?
Answer:

Staking is not required for most newly planted trees.  However, large trees and those planted in windy, exposed sites may require staking.  If staking is necessary, allow the trunk to move or sway for proper trunk and root development....

Question:
When is the best time to sow grass seed?
Answer:

Late summer (mid-August to mid-September) is the best time to establish a lawn from seed in Iowa.  Late summer seeding has several advantages over spring seeding.  The seeds of cool-season grasses germinate quickly in the warm soil of...

Question:
How do I know when a watermelon is ready to harvest?
Answer:

Harvest watermelons when the underside or belly of the fruit turns from a greenish white to buttery yellow or cream.  This color change is especially pronounced on the dark green skinned varieties.  In addition, the fruit tends to lose...

Question:
There is a pile of sawdust-like material at the base of a large tree. What could be the problem?
Answer:

It’s likely the pile of sawdust-like material was produced by carpenter ants.  Carpenter ants commonly nest inside older, hollow trees or in trees with dead limbs or branches.  Carpenter ants do not eat wood.  However, they...

Question:
Is it possible to control downy mildew on impatiens?
Answer:

In landscape plantings, control of downy mildew on impatiens with fungicides is not practical. Sanitation is the best management strategy for this disease. Remove and destroy infected plants as soon as they are noticed to reduce the spread to...

Question:
When should radishes be harvested?
Answer:

Radishes can be harvested 3 to 5 weeks after planting.  Periodically check their development by pulling one or two plants as they approach maturity.  Harvest radishes when roots reach useable size (about 1 inch in diameter). ...

Question:
What effects will construction activities have on nearby trees?
Answer:

Construction of buildings, patios, garages, driveways, sidewalks, and roads often compromises the growing environment of nearby trees.  The majority of a tree’s roots are located in the top 12 to 18 inches of soil and often extend well...

Question:
What is the proper way to divide peonies?
Answer:

September is the best time to divide peonies.  By September, peony plants have been able to store adequate food reserves in their roots.  Also, the replanted divisions have several weeks to get reestablished at their new sites before...

Question:
When should I harvest tomatillos?
Answer:

Gardeners should be able to begin harvesting tomatillos 75 to 100 days after transplanting.  For best flavor, harvest tomatillos when the husk changes from green to tan while the fruit is still green.  The size of the husk and fruit, as...

Question:
There are brown streaks in my apples. What is the cause and how can it be prevented?
Answer:

The brown streaks in the apples are probably due to the apple maggot.  The apple maggot is the most serious insect pest of apples in Iowa.  Apple maggot damage appears as knobby, misshapen fruit with small pits or blemishes on the fruit...

Question:
There are horn-shaped, foul-smelling objects growing in my mulched flower beds. What are they?
Answer:

The foul-smelling objects are likely stinkhorns. Stinkhorns are a type of fungus or mushroom. The common name is derived from their appearance and smell. Stinkhorns usually appear in cool, wet periods in late summer and early fall.

Several...

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:
What are jostaberries?
Answer:

Jostaberries are a cross between black currants and gooseberries.  Plants are vigorous and may grow to a height of 6 to 8 feet.  Jostaberry fruit are similar in size to gooseberries and black in color.  Plants possess excellent...

Question:
How do I care for a grapefruit tree?
Answer:

Grapefruit and several other types of citrus can be grown indoors in Iowa.  Indoors, place citrus plants in a sunny south or west window.  Water plants regularly when growing in spring and summer, less often in winter.  In spring...

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:
When should I harvest raspberries?
Answer:

Raspberries are ripe when the fruit are fully colored.  Also, ripe berries slip easily from their receptacles, which remain on the plant.  If possible, harvest in the early morning hours before heat builds up in the fruit. ...

Question:
Should I wrap the trunks of newly planted trees?
Answer:

Wrapping protective materials around the trunks of newly planted trees is usually not necessary.  There appears to be little or no benefit to tree wraps.  If you do decide to use a tree wrap, place it around trees in fall (November) and...

Question:
When is the best time to lay sod in Iowa?
Answer:

Sod can be successfully installed from spring to fall.  However, spring (late April and May) and late summer/early fall (September and October) are the best times to install sod in Iowa.  

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