In The Garden This Week:The Calendar Says It's Summer

Multiflora Rose: Have you noticed this week the beautiful and bountiful flowering multiflora roses? They are distinctive as climbing white roses flowing everywhere in the yard or along the highways or just about anywhere they can get a start. If they can be controlled, they can make a nice screen. But watch out! They are one of the most invasive plants around at this time of the year. I was cutting back some this week because they had totally overwhelmed a bed of four Spirea that I have had for a little over 20 years. About halfway through this task (and after acqiring many scratches from the thorns) I encountered a robin's nest with two babies waiting for me to feed them, as their mother hovered noisily above. So that made me decide to come back to finish that job another day.

I also cut multiflora roses out of a 7-foot viburnum where the multiflora rose was an additional foot high. It was a messy but an essential job, for the multiflora roses would easily take over that spot eventually.

So be wary of the multiflora rose with those beautiful white flowers. The plant grows easily and it one of the most invasive plants at this time of the year.

Rain Problems: Rhode Island gardeners (and farmers as well) have been adversely affected by the significant amount of rain that we have had so far in June. This has slowed the growing season for most vegetables and flowers. It had also brought several fungal diseases such as black spot on roses and powdery mildew on ninebark and other plants. It may be necessary to to consider the use of a fungicide to solve these problems. If so, choose the fungicide very carefully. Read the label closely. This is especially true for plants that produce food that you intend to eat. Do you really want to spray a copper-based fungicide on vegetables? The most important part of the label on control materials is not what this control will do to solve your problem. But rather what is most important is that almost microscopic description of what the control is made up of.  In most cases that label will indicate a very small amount of a chemical followed by a line which says something like "inert ingredients". That is the material that is usually 98-99%. Do not be comforted by that. Unfortunately the government does not require an explanation of what "inert" means. Sometimes these can contain manganese, zinc, cadmium and chromium amog others. Many of these already exist in the soil in more than sufficient amounts and your plants need no more of them.

Organic controls do exist and they will be covered in a future blog. For now you can pick off leaves that are affected by fungi, bag them and get rid of them. Do  NOT put them in the compost pile, for the will continue to affect your healthy plants.

Finally, it is a very easy process on the internet to look up the chemical used in various  fungicides (as well as pesticides and insecticides). Read carefully what the USDA or various university sites (those whose address ends in ".edu") say about the effect of that chemical.

As for insects, keep in mind that over 90% of insects are beneficial. Do  not apply something that will kill bees. We desparately need them for pollinating a vast variety of plants. If you must spray something that is harmful to bees (like Sevin) spray it in the evening after the bees have gone to bed.

Asiatic Lililies: These beautiful flowers are really popping open ever day. What a gorgeous display of various colors they are showing. If your lilies are not opening (and if the plants do not look healthy), the culprit is probably the lily leaf beetle. They have been laying eggs which are obvious on the underside of the leaves. If you have a problem you should inspect your lilies carefully and see if you have the beetle. You can spray your lilies with a combination of pyrethrin (organic-for the larval stage) and rotenone (close to organic-for the hard-shelled beetle). Many nurseries sell a combination of these is a concentrate and it is easy to apply with a spray bottle. Don't wait! Attack now!

Soil Testing: It is not too late to get your soil tested if you are having a problem with your plants or lawn. Knowing the pH and the overall texture of you soil will make or break your gardening or lawn success. Even after plants have begun to mature, a soil test will indicate a great deal toward your future horticultural success.

A weekly soil testing/gardening kiosk is set up at Paradise Valley Park in Middletown (Paradise and Prospect Avenues) every Saturday from 11-1, rain or shine until the end of September. Bring your soil sample or your questions about weeds or insects for identification. This is a free service provided by the URI Master Gardeners. Or you can contact us at gardeninginformationri@gmail.com.

Feel free to add a question or comment below. More next week.