Frequently Asked Questions

Question:
When can I harvest eggplant?
Answer:

Begin harvesting the large, oval varieties when the fruit are 2 inches in diameter.  Continue to harvest the fruit until they are 4 to 6 inches across.  At the proper harvest stage, the fruit will be firm and shiny.  Overmature...

Question:
When can I transplant jack-in-the-pulpit?
Answer:

Jack-in-the-pulpit (Arisaema triphyllum) can be transplanted after the foliage dies back in late summer.  Jack-in-the-pulpit performs best in moist, organic-rich soils in partial to heavy shade.  The corm-like tubers should be...

Question:
How can I keep raccoons out of my sweet corn?
Answer:

The most effective way to prevent damage to the sweet corn crop is to encircle the area with an electric fence.  A two-wire fence with one wire 4 to 6 inches above the ground and the other at 12 inches should keep the raccoons out of the...

Question:
Can I plant my Easter lily outdoors after it is done blooming?
Answer:

Individuals wishing to save their Easter lily (Lilium longiflorum) should place the plant in a sunny window after flowering.  Continue to water the plant when needed.  Fertilize once every 2 weeks with a dilute fertilizer...

Question:
Can I place weeds and diseased plant debris from the vegetable garden in the compost pile?
Answer:

It would be best to place weeds that are producing seeds and diseased plant debris in biodegradable bags and have the material picked up and composed by a municipal or commercial composting facility.  The temperatures in home compost piles...

Question:
The foliage at the ends of the branches on my honey locust are turning brown. Why?
Answer:

The browning of the honey locust foliage is probably due to the mimosa webworm.  Damage occurs when the caterpillars tie honey locust leaflets together and feed on the foliage inside the tightly compressed, protective webs.  Affected...

Question:
How should I water a newly sodded lawn?
Answer:

A newly sodded lawn should be watered once or twice a day for the first 7 to 10 days.  Apply enough water to moisten the sod and upper 1 inch of soil.  The sod should root to the soil in about 10 days.  At this point, gradually...

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:
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:
There are round, circular spider webs are on my lawn. What should I do?
Answer:

The horizontal circular webs were created by various spiders collectively called grass spiders.  They are harmless to the grass and ecologically beneficial as predators.  The webs accumulate between rain showers and mowings.  They...

Question:
How can I tell dead canes from live shoots when pruning raspberries in late winter?
Answer:

Dead raspberry canes will be white to gray in color.  When dead canes are pruned, the tissue inside the stem will be tan to brown and dry.  Live canes will be brown to purple in color.  The tissue inside the stem will be white to...

Question:
How often should I water plants in hanging baskets?
Answer:

Plants in hanging baskets need to be watered frequently (especially in summer).  Potting mixes are light, well-drained, and dry out quickly.  Plus, hanging baskets may contain several plants.  In general, water plants in hanging...

Question:
How can you tell when a muskmelon is ripe?
Answer:

The fruit of the muskmelon or cantaloupe is mature when the stem slips easily from the melon with slight pressure.  The melon is not ripe if the stem has to be forcibly separated from the fruit.  Other indicators of maturity are based...

Question:
Can the butterfly weed be divided?
Answer:

The butterfly weed (Asclepias tuberosa) is a member of the milkweed family.  Plants grow 2 to 3 feet tall and produce flat-topped clusters of bright orange flowers from July through September.  Their flowers attract several...

Question:
When should I harvest sweet corn?
Answer:

Sweet corn should be harvested at the milk stage.  At this stage, the silks are brown and dry at the ear tip.  When punctured with a thumbnail, the soft kernels produce a milky juice.  Over-mature sweet corn is tough and doughy....

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:
How do I control weeds in my garden?
Answer:

Herbicides can be used to supplement cultivation, hand pulling, and mulches. 

Hand Pulling

Cultivation, hand pulling, and mulches are the primary means to control weeds in the home garden. 

Cultivation and hand...

Question:
There are big, hairy worms and tent-like structures in my walnut tree. What are they and how do I get rid of them?
Answer:

The “worms” are likely fall webworms.  Fall webworms are hairy, tan to yellow caterpillars.  As they feed, fall webworms construct tents or webs at the ends of branches.  Tents are initially small, but the caterpillars enlarge the...

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:
I have several rows of grapevines. What would be a good cover crop between rows?
Answer:

Kentucky bluegrass is an excellent choice.  Bluegrass provides good cover, yet is less competitive than other cover crops.  Late summer (mid-August to mid-September) is the best time to establish bluegrass by seed.  Do not sow...

Question:
There are several large surface roots around my shade tree. Can I safely cover these roots with soil?
Answer:

Trees have shallow roots. The vast majority of a tree’s roots are located in the top 12 to 18 inches of soil.  As the tree roots grow, some of the larger roots near the soil surface may emerge from the ground. While many individuals regard...

Question:
Large areas of my lawn have turned orange. Why?
Answer:

The orange color is likely due to rust.  Rust is a fungal disease.  It can be diagnosed by walking across the lawn in white shoes.  As you walk across the lawn, bright orange spores of the rust fungus will rub off onto the shoes,...

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:
How frequently should I water annuals in containers?
Answer:

The frequency of watering may vary considerably from container to container.  Watering frequency depends on the size and type of container, composition of the potting mix, plant species, and weather conditions.  Some plants, such as...

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...

Pages