• Low maintenance
  • Blooms from spring to frost
  • Sun to Part Sun
  • Hardy in zones 5-11
  • Mature size: 3-4′ w x 3-4′ h
  • 7 great colors to choose from

The post Rose Knockout appeared first on The Good Earth Garden Center.

What is Rose Rosette Virus?

One of our beloved landscape plants, the rose, has been increasingly affected by this virus, which is spread by tiny wind transferred mites.  Symptoms include thickened stem growth, excessive thorns, witches’ broom growth at end of stems, branch die-back, discolored and distorted leaves.

The above image shows the excessive thorn development on an affected rose. The symptoms of the virus can be fairly easily seen year round; this picture was taken in January of 2020.  This particular rose showed no symptoms all spring, summer and even fall.  After a late fall warm spell, the rose sprouted symptomatic new growth.

Prevention of Rose Rosette Virus

1. Prune around Valentine’s Day each year.  This will remove mites that might be overwintering in flower buds or seed heads. Dispose of pruned material; avoid composting in case mites or the virus is present. Tips on how to properly prune roses can be be found in this video.
2. When doing yard clean-up, avoid using blowers.  As we mentioned above, mites are often wind transferred and gusts of air can spread them through the landscape.
3. Space roses well. Plant so that at mature size, leaves from one plant won’t touch another.  This could reduce the occurrence of mites walking from one plant to another.  Proper spacing also increases air flow which will help reduce the occurrence of other disease issues such as black spot.
4. If you have been around infected roses, wash your hands, gloves, and clothes before working in the garden. All could have picked up mites. While the virus that causes rose rosette isn’t able to survive long outside of the plant, virus spreading mites may be present on your shovel or pruners.  Clean tools with household disinfectant or a bleach solution before using them in the garden again. Overkill? Maybe, but mites are so tiny (1/200th of an inch) that they can easily hitch a ride on you or your tools.
5. When designing your landscape, consider using alternative plants (see list below).  There aren’t any other plants that offer the exact same features as a KnockOut or Drift rose but there are some wonderful re-blooming shrubs and others with outstanding foliage color.

The above image shows witches broom growth, which is the tight cluster of stems, leaves, buds and even flowers near the end of branches. This odd growth pattern is obvious even in winter months. If you think your plant may have rose rosette, take pictures and email them to us or bring a sample for identification (keep sample contained in plastic bag to help prevent spread).

Control

Unfortunately, there is no cure for this virus and affected plants will need to be removed and put in the garbage. Do not compost or burn the affected materials.  For existing, unaffected roses, treat with dormant oil after cutting back in February, which could help control overwintering mites. Remove any fallen leaves or debris. Spraying with harsher chemicals could reduce the beneficial insects that feed on the mites.

If you have just one plant showing symptoms, remove that plant only and follow the prevention tips above to help control the spread. Although this disease can take years to kill a plant, during this long decline, many other roses may be infected by it (mites being wind transferred to unaffected roses). We recommend removing symptomatic plants as soon as they are identified as such. It will not help to prune out only symptomatic branches since the virus spreads throughout the entire plant, including the roots. Remove the entire plant, including as many roots as possible.

There are a few resistant rose varieties, including Top Gun, however, no variety has been proved 100% resistant. Research is ongoing.  It would be best to avoid replanting with roses for at least one year if your landscape has been overcome with this virus.  This is due to the fact that the virus may still be in remaining roots left in the ground after removal.  Mites may have also already infected nearby roses, meaning that the virus could continue to spread onto newly planted roses.

There is conflicting information out there regarding whether treating healthy roses for the only known vector of this virus (eriophyid mite, Phyllcoptes fructiphilius) could slow down the spread of rose rosette.  This particular mite may or may not be controlled by organic or nonorganic miticides (again, conflicting information from various extension organizations). If you would like to try to control this mite with nonorganic pesticides, the University of Arkansas Division of Agriculture Research and Extension Service recommends those with one of the following active ingredients in their fact sheet (FSA-7579): abamectin, bifenthrin, carbaryl, deltamethrin, imidacloprid, malathion or permethrin. In general, mites may also be managed using pyrethrum, which may be desirable for organic control.

Alternative Plants

While no plant can completely replace the April to November blooming period of KnockOut and Drift roses, here are several wonderful, hardy plants that offer either bright, long season blooms or colorful foliage all season long.

Weigela

Encore azalea

Dwarf or semi-dwarf butterfly bush

Dwarf loropetalum

Dwarf crapemyrtle

Kaleidoscope abelia (and other dwarf varieties with foliage color)

Compact nandina (several varieties)

Recovering from a substantial rose loss?  Our team will be here to offer suggestions when you are ready to replant.

The post Rose Rosette Virus Identification and Control appeared first on The Good Earth Garden Center.

Warm Wet Weather

Warm, wet weather brings on fungus…and we get our share of this kind of weather, which means our landscape plants and lawns often have fungus issues.  Let’s take about landscape plants first!  So what does a fungus look like?  Usually, the symptoms of fungus are easily identifiable…round black spots, irregular brown spots or a downy, white dusting on leaves.  Some of our most beloved landscape plants are susceptible to fungus including Indian Hawthorn, Roses, Lilacs, Hydrangeas, Columbine and Dogwood trees to name a few.  While some plants are more susceptible, keep in mind that pretty much any plant could get a fungus if the conditions are conducive and the fungus spores are present. However, there are some things we can do to help avoid fungus infections.

Good Air Flow

Space plants based on mature size.  Properly spaced plants have more air flow between them, which keeps foliage drier both after a rain and after irrigation applications.  For example, KnockOut Roses can grow to at least four foot tall.  Ideally, they would be spaced about five feet apart, from center to center, at planting.  We understand the temptation to plant closer together when the new, young plants are small, but the extra maintenance involved with pruning and harder control disease outbreaks just aren’t worth it!

Proper Watering Timing

We mentioned irrigation above; the amount of water is less important than when you water, at least when trying to avoid fungus issues.  Watering early in the morning is ideal so that the foliage can dry fast as the sun and wind pick up for the day.  Conversely, watering in the evening provides the perfect circumstance for fungal growth…hours of water sitting on foliage in a dark environment.  Bottom line, water in the early morning and space your plants out properly.

Prevention and Control of Fungus in Landscape Plants

That covers all that we can control; the environment and weather have big roles too.  Obviously, in an area with warm, humid spring and fall seasons, no matter how carefully you have taken care of your plants, fungus is unavoidable. Once a plant is infected, the best solution is to treat it with a systemic fungicide such as Ferti-Lome Liquid Systemic Fungicide.  For roses, there is also a product from Bayer called All in One Rose & Flower Care that includes a fungicide as well as a fertilizer and insect control product; this works well as a preventative treatment.

Apply fungicide sprays when the foliage is completely dry and will remain dry for about 24 hours; this will allow it to be fully absorbed.  Take note of how long the products treats for; additional sprays might be necessary during prolonged wet spells and while conditions are good for fungal growth.  The systemic fungicide will be absorbed and distributed throughout the plant, protecting new leaves from being infected and kill spores present on leaves which will reduce spreading.  Non-systemic fungicides such as Bonide’s Copper Fungicide will kill active fungus spores already on leaves and is good for edibles.

Keep in mind that the treatment process can take several applications and infected leaves will most likely turn yellow and fall off.  Be sure to remove and dispose of infected leaves to help reduce spread of fungus.  Plants that are susceptible to fungus can be sprayed at a preventative rate; read labels carefully, the rate for preventative sprays is different than the curative rate.

Prevention and Control of Fungus in Lawns

Now on to the lawn!  Lawn fungus symptoms include large circular or slightly irregular, thinning, brown spots that grow in size each year.  As with landscape plants, there are some control measures we can put in place before the occurrence of fungus to help reduce the chances of infection and impact the recovery time.  Fertilize with slow release fertilizer instead of a fast release, high Nitrogen fertilizer.  Water lawns deeply, less frequently, as opposed to more frequent, shallow waterings.  This will encourage better root growth.  Provide good drainage, both on the surface and subsurface of the lawn areas.  Good drainage insures that water can quickly move out of lawn areas.  As we talked about above, clearly we aren’t in control of the rain and temperatures.  However, we can control the fertilization and water we apply, as well as address drainage.

Once symptoms of fungus are visible, treat as soon as possible with Bonide Infuse Systemic Disease Control or Ferti-Lome F-Stop granules or Ferti-Lome Liquid Systemic Fungicide, available as a liquid spray.  Treat the entire lawn area to help control spread.  This will need to be done while conditions for fungal growth are present and for the next few years as well.  Preventative applications on lawns before the wet, warm season are helpful.  Apply in March at preventative rates as the warm season grasses start greening up.

For plant materials that are too large to spray, keep in mind that most foliar fungus diseases on trees and shrubs will cease being active when we reach temperatures consistently above 90 degrees.  For large healthy plants, the issue will more of an aesthetic one than one that could cause plant death. The same is true for shrubs like hydrangeas; it’s more unsightly than dangerous but if let go too long for too many years, it could cause a decline of plant health.

The post Prevent & Control Fungus in Landscapes appeared first on The Good Earth Garden Center.

Why prune?

Spring pruning is done for several purposes, such as to shape, encourage new growth, and clean up. Not all plants require pruning so ask questions and have a game plan before getting the tools out. Keep the goal in mind when pruning; it’s easy to get carried away! A good rule of thumb is to remove no more than 30% of the plant when pruning…more than that can stress the plant, causing a decline in health and an increase in pests.

When to prune in Arkansas?

Knowing what to prune and when is crucial. Prune ornamental grasses, crepe myrtles, most roses, fruit trees and evergreen perennials in February. Evergreen shrubs and groundcovers can be pruned in March. Wait to prune spring flowering shrubs such as azaleas and forsythia until after they bloom…otherwise the blooms will be removed. Visit our gardening calendar for more complete schedule!

Don’t be guilty of Crape Murder!

As mentioned above, it can be easy to remove too large a portion of the plant. Crapemyrtles are often pruned too much and poorly…this practice is called ‘crape murder’. These trees don’t require any pruning but are often cut back severely, causing large unattractive ‘knees’ or knots to form. Learn how to properly prune crape myrtles by on this post and You Tube channel. Also, check out How to Control Crapemyrtle Bark Scale, a very destructive pest.

How to Prune?

Hand pruners, shearers, loppers, chain saws…just what is needed for proper pruning? Felco hand pruners will work on most shrubs, grasses and perennials. Use loppers on larger limbs and branches. Before pruning, check tool blades and sharpen as needed.  And for more in-depth information, come see us!

The post Spring Pruning Tips for Arkansas! appeared first on The Good Earth Garden Center.