Ash rust is probably responsible for the orange growths on your ash tree. Ash rust is caused by the fungus Puccinia sparganioides. The fungus produces conspicuous swellings on leaves, petioles, and twigs. Infected…
Ash rust is probably responsible for the orange growths on your ash tree. Ash rust is caused by the fungus Puccinia sparganioides. The fungus produces conspicuous swellings on leaves, petioles, and twigs. Infected…
Melons are relatively easy to grow. Their basic requirements are full sun and a fertile, well-drained soil. The planting site should receive at least 6 hours of direct sun each day. Heavy, poorly drained soils can often be…
The small, white, popcorn-like objects are likely cottony maple scale. Cottony maple scale is an insect. It is most commonly found on silver maple trees. However, it can also be found on other maples, oak, linden, hackberry,…
Proper pruning of purple raspberries promotes high yields, helps control diseases, and facilitates harvesting and other maintenance chores.
In March or early April, remove all small, weak canes, leaving only 4 or 5 of the largest,…
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…
The Emerald Ash Borer (EAB) is an exotic destructive pest that kills all native ash trees (Fraxinus). The loss of ash trees significantly impacts the urban tree canopy. While treatment options are available, some trees cannot be treated…
Several organic materials can be used as a mulch around tomato plants. Suitable mulching materials include:
Gardeners can choose from numerous canna varieties. Some of the more popular varieties are listed below.
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…
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.…
There are several cultural or management techniques the gardener can use to reduce weeds in the vegetable garden.
Cool-season annuals are annual plants that prefer cool temperatures, growing best in spring or fall. Many are tolerant of a light frost often surviving down to 28°F or sometimes even 25°F with little damage to flowers or leaves.
Since…
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…
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…
Herbs grow best in the same conditions as most vegetables. Plant in full sun with at least six hours of sunlight a day. While not ideal, some species will grow in part-sun, receiving two to four hours of direct sunlight each day. Herbs will grow…
Many home gardeners choose to avoid the use of herbicides in vegetable gardens since they are growing edible crops. In certain situations, however, a gardener can use herbicides to supplement other weed control strategies. Most…
There are dozens of different species and varieties of herbs that can be grown, but a few are particularly easy to grow in Iowa.
Basil (Ocimum basilicum) is an annual started easily from seed each spring.
Cilantro (…
Grapevines can be grown on a wide range of soil types. Best growth and yields are obtained in well-drained soils. Avoid soils that are persistently wet during the growing season. Highly fertile…
Tomatoes perform best in fertile, well-drained soils. Avoid heavy clay soils and poorly drained sites. For best yields, tomatoes need at least 6 hours of direct sun per day. To discourage Septoria leaf spot, early blight, and…
Cedar-apple rust is likely responsible for the yellow spots on the crabapple leaves. Cedar-apple rust is a fungal disease. The fungus requires both a crabapple or apple and a cedar (juniper) to complete its life cycle. Crabapple…
Thatch is the layer of dead and living plant material that forms between the soil surface and green vegetation. It is composed of shoots, crowns, and roots. Thatch, to some degree, is present in all lawns. However, when thatch…
Periodical cicadas emerge in 13- or 17-year cycles depending on the brood. These broods emerge in specific geographic regions. Occasionally, two broods will emerge in the same year, and more rarely, there can be some overlap in the geographic…
Kentucky bluegrass and other cool-season grasses thrive in the cool weather of spring and fall. Hot, dry conditions in summer are stressful for cool-season grasses. Kentucky bluegrass lawns should be mowed at a height of 3 to 3½…
Sweet corn performs best in fertile, well-drained soils in full sun. Standard sweet corn (su) varieties may be planted in late April in central Iowa. It’s generally recommended that sugar enhanced (se) varieties be planted 1 week…
Variety and cultivar are two terms often used interchangeably by gardeners and horticulturists, but they are not the same thing.
Both are part of the scientific name. Both appear after the specific epithet (second term in a scientific name…
We often use the words herb and spice interchangeably. Herbs and spices are obtained from plants. (Salt is neither a spice nor an herb. It is actually a mineral.) Herbs and spices are used primarily for adding flavor and aroma to food. And both…
Ground ivy and creeping charlie are two different common names that refer to the same plant (Glechoma hederacea). Henbit (Lamium amplexicaule) is a different species that looks similar. It is important to tell them…
The small, blue-flowering plant is probably Siberian squill (Scilla sibirica). Siberian squill is an early spring flowering bulb. Plants typically bloom in early to mid-April in Iowa. Bright blue flowers are produced on…
Do not mow shady areas less than 3 inches in height. Because of the lower photosynthetic rates in shady areas, the turfgrass plants need a large leaf surface to manufacture adequate amounts of food. The recommended mowing height for…