Frequently Asked Questions

Question:
What are hardwood stem cuttings?

Answer:

Plants can be propagated by a number of different methods.  Hardwood stem cuttings utilize shoots of the previous year’s growth on trees, shrubs, and vines to produce new plants. 

Question:
Which plants can be propagated from hardwood stem cuttings?
Answer:

Several woody trees, shrubs, and vines can be propagated by hardwood stem cuttings.  Plants that can be propagated by this method include willow, poplar, dogwood, forsythia, wisteria, grape, currant, gooseberry, and elderberry. 

Question:
What materials are needed to make hardwood stem cuttings?
Answer:

Materials needed to make hardwood stem cuttings include a pruning shears, rooting hormone, plastic bag, and sphagnum moss or wood shavings.  Use the pruning shears to collect cutting material and also cut the shoots to the proper length....

Question:
When should material for hardwood stem cuttings be collected?
Answer:

Material for hardwood stem cuttings should be collected in late winter (when the plant material is dormant) from wood of the previous season’s growth.  In Iowa, hardwood stem cutting material should be collected in late February or early...

Question:
What is the proper size of hardwood stem cuttings?
Answer:

The length of most hardwood stem cuttings varies from 4 to 12 inches.  However, the cuttings of some plants may be up to 30 inches in length.  The diameter of hardwood stem cuttings typically ranges from ¼ to 1 inch.  Each cutting...

Question:
What is the procedure for rooting hardwood stem cuttings?
Answer:

After cutting the material to the proper length, dip the bottom of each cutting in a rooting hormone.  Gather the cuttings together (placing all the tops in one direction) and secure them with twine or rubber bands.  Place the bundled...

Question:
Are there any trees or shrubs that bloom in winter?
Answer:

While most trees and shrubs bloom in spring or summer, witch hazels are a notable exception. Common witch hazel (Hamamelis virginiana) blooms from mid-October to early December.  Vernal witch hazel (Hamamelis vernalis) and...

Question:
The flower and vegetable plants that I start indoors get tall and spindly. Why?
Answer:

Tall, spindly growth is a common problem when growing transplants indoors. Poor (insufficient) light, excessive watering, high temperatures, excessive fertilization, and crowded conditions are factors that contribute to spindly growth.

...

Question:
Some of the seedlings that I start indoors collapse and die shortly after germination. Why?
Answer:

Damping-off is probably responsible for the collapse and death of your seedlings. Damping-off is caused by several different fungi. Environmental conditions associated with damping-off are poorly drained potting soil, overcrowding, and excessive...

Question:
When should I sow my flower and vegetable seeds indoors?
Answer:

The growth rate of the seedlings and the outdoor planting date determine when to sow seeds indoors.  The crop time (number of weeks from sowing to planting outdoors) for several popular flowers and vegetables are as follows: 10 to 12 weeks...

Question:
The seeds that I start indoors germinate poorly. Why?
Answer:

Poor or erratic germination of seeds may be caused by improper planting (for example, planting too deeply), uneven moisture, and cool temperatures. 

Fine seeds and those seeds which require light for germination should be sown on the...

Question:
When should I remove the mulch on my strawberry bed?
Answer:

To reduce the chances of crop damage from a late frost or freeze, leave the mulch on as long as possible.  Removing the mulch in March may encourage the plants to bloom before the danger of frost is past.  Temperatures of 32 degrees...

Question:
When should I apply a dormant oil spray to my fruit trees?
Answer:

Dormant oil sprays are highly refined petroleum products that are mixed with water and applied to trees and shrubs to control aphids, spider mites, and scale.  Dormant oils destroy pests by suffocating them.  When applied properly, the...

Question:
When should I prune my fruit trees?
Answer:

Late February to early April is the best time to prune fruit trees in Iowa.  Summer pruning of fruit trees is generally not recommended.  However, water sprouts (rapidly growing shoots that often develop just below a pruning cut) can be...

Question:
I placed soil around the base of my hybrid tea roses in fall. When should I remove the soil?
Answer:

Remove the soil in late March or early April in southern Iowa, mid-April in northern portions of the state.  A frost or freeze in early spring shouldn’t harm the roses. 

After removing the soil, prune out any dead wood. ...

Question:
It's only February, but my tulips are coming up. What should I do?
Answer:

Tulips, daffodils, and other spring-flowering bulbs normally begin emerging from the ground in March or early April in Iowa.  However, mild winter weather can encourage premature growth.  The early emergence of spring-flowering bulb...

Question:
I received a miniature rose for Valentine's Day. How do I care for it?
Answer:

Miniature roses need direct sun.  In the home, place the miniature rose in a south or west facing window.  Rotate plants once or twice a week to promote even growth. 

Miniature roses also require a consistent moisture supply...

Question:
I recently received a flowering azalea as a gift. How do I care for it?
Answer:

In the home, place the azalea in a brightly lit, cool location.  An ideal site is one near a window that receives bright light (but no direct sunlight) and temperatures of 60 to 65 degrees Fahrenheit. 

An important aspect of...

Question:
Is it possible to save tulip bulbs that have been forced indoors?
Answer:

Tulips, hyacinths, and most other spring-flowering bulbs that have been forced indoors are usually discarded after flowering.  Most won’t bloom again when planted outdoors.  Daffodils are an exception.  Daffodils are more vigorous...

Question:
When should I prune my shrubs?
Answer:

The proper time to prune deciduous and evergreen shrubs is determined by the plant’s growth habit, bloom time, and health or condition. 

Spring-flowering shrubs, such as lilac and forsythia, bloom in spring on the growth of the...

Question:
When should I prune spring-flowering deciduous shrubs?
Answer:

Spring-flowering shrubs, such as lilac and forsythia, bloom in spring on the growth of the previous season.  The plant’s health or condition determines the best time to prune spring-flowering shrubs. 

Neglected, overgrown spring-...

Question:
When should I prune summer-flowering deciduous shrubs?
Answer:

Summer-flowering shrubs, such as potentilla, Japanese spirea, and panicle hydrangea, bloom in summer on the current year’s growth.  Prune summer-flowering shrubs in late winter or early spring.  The pruned shrubs will bloom in summer on...

Question:
When should I prune “non-flowering” deciduous shrubs?
Answer:

All shrubs flower.  However, the flowers of some deciduous shrubs, such as winged euonymus (burning bush), alpine currant, and fragrant sumac, are small and inconspicuous.  These shrubs possess attractive foliage, fruit, bark, or some...

Question:
When should I prune evergreen shrubs?
Answer:

Prune narrow-leaved evergreen shrubs, such as juniper and yew, in early April before new growth begins.  Light pruning may also be done in mid-summer.  Avoid pruning narrow-leaved evergreens in fall.  Fall pruned shrubs are more...

Question:
How often should fruit trees be pruned?
Answer:

Fruit trees should be pruned on an annual basis.  Annual pruning of young (non-bearing) fruit trees develops a strong framework and desirable tree shape.  Annual pruning of bearing trees maintains tree vigor, maximizes fruit yields, and...

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