To encourage vigorous growth and abundant bloom, hybrid tea, floribunda, and grandiflora roses should be fertilized two or three times a year. Fertilizer applications can be made in early spring (immediately after pruning), during the first…
The upper portions of hybrid tea, grandiflora, and floribunda roses typically die due to exposure to low winter temperatures and extreme temperature changes. When the winter protection is removed from these roses in early spring (late March…
While most shrub or landscape roses are winter-hardy in Iowa, there is still typically some branch die-back over winter. Gardeners should prune out the dead wood just as the new buds are turning green and breaking in spring - typically…
A potted miniature rose can be kept as a houseplant through the winter months. Bring the plant indoors before a hard freeze. Place the miniature rose in a sunny window or under artificial lighting. Avoid sites near cold drafts…
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. Live…
No. Pruning stimulates new growth. That new growth will not have an opportunity to properly harden off before winter leaving it vulnerable to more winter damage.
Even established growth that has properly hardened off will see…
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…
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…
Modern roses, such as hybrid tea, grandiflora, and floribunda roses, are propagated by budding. A single bud is removed from the desired variety and inserted onto a hardy rootstock. The bud union (the knob-like swelling at the base of…
Deadheading or the removal of faded flowers is done to encourage additional bloom on hybrid tea and other repeat-flowering roses. Hybrid tea roses usually have one or two 3-leaflet leaves immediately below the flower. Next (lower down…
When plants produce a chemical that prevents the growth of other plants, it is called allelopathy.
Black walnut is a common woodland and landscape tree in the Midwest that produces an allelopathic compound called juglone which is…
The upper portions of modern roses, such as hybrid teas, floribundas, and grandifloras, typically winterkill due to exposure to low winter temperatures and extreme temperature changes. Gardeners should prune out the dead wood after the…
Old garden roses, hybrid rugosas, and other hardy shrub or landscape roses often survive Iowa's winters with little or no winter injury. If there is any winter injury, it can be pruned back to live wood just as the new buds are turning…
In Iowa, early spring (before the plant begins to leaf out) is the best time to transplant a rose. The optimal time period is normally late March to mid-April. Dig up the rose using a shovel or spade and replant immediately. …
