It ain’t been your average year for plant health

June 3, 2012

The doctor is in the house…Dr. Earth!

It’s not just that Dr. Earth is a great sponsor of The Mike Nowak Show, though I certainly appreciate their support. There are several other things that make this company so interesting. One is the zeal with which its founder, Milo Shammas, spreads the word of organics, living soil and what he calls “probiotics.” From the Dr. Earth website:

The soil is alive! Below our feet and invisible to the naked eye, tiny microbes— the great digesters of the earth—constantly break down organic material into a more usable forms that plant roots can identify, absorb, and ultimately incorporate for new growth. This material includes complex organic compounds, such as tannins, lignins, proteins, carbohydrate, cellulose, pectin, etc.

Healthy soil should contain no less than 10,000,000 bacteria per gram. The presence of microbes ensures that nutrients are made available to plants at a steady rate. While the plants are actively growing—and requiring more nutrients—so do the microbes in the soil. As the weather warms, both the plant and microbes respond at a similar rate. The microbes become increasingly active in their role of breaking down organic materials into forms more readily absorbed by the growing plants that need extra nutrition. As the weather cools—and plants require less nutrition—so do the microbes. The reduction in their activity means fewer nutrients in the soil are being released to the plants. In this way, the soil can rebuild food reserves. This self-regulating cycle has occurred for millions of years as part of the wisdom of nature.

Microbes also help to stabilize the soil by physically binding soil particles together; they release a by-product called glomalin that acts as a “glue,” binding mineral particles and organisms to each other. This contributes greatly to soil aggregation. All of these processes happen naturally in a healthy, productive soil.

Another thing that is so interesting about the Dr. Earth products is how highly respected they are by so many people in the horticultural industry. The gospel of Dr. Earth is spreading, and I welcome Millo Shammas back to the show to talk about the benefits of going organic in your garden. By the way, don’t forget that you can get organic gardening advice and other information on the Dr. Earth Facebook page.

Speaking of great advice…here are Jennifer and Wally!

If there was ever a year in which you needed a couple of gardening experts on your team, this is undoubtedly it. Starting with a string of record-shattering warm temperatures in March, through the cold, wet April, to the dry, warm, then very hot May…and then a 50 degree temperature drop in about three days. Whew! No wonder the diseases and insects are a bit off the charts this year.

The Morton Arboretum’s Plant Health Care Report for June 1 reveals that, as of May 31, we are at 692 base-50 growing degree days (GDD), which is 334.5 GDD 50 ahead of 2011 at this time. In May it rained 2.64 in., which brings us to 9.57 in. for the year (compared to 15.4 last year at this time), based on observations at the Morton Arboretum.

In case you’re wondering what growing degree days are, you can click on the link to see the mathematical formula, or you can be content with knowing that GDD are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and pest development rates such as the date that a flower will bloom or a crop reach maturity, or when a pest will emerge to cause trouble.

So, as you can see, we’re 334.5 GDD ahead of last year, which is significant. And because the temperatures went up early and came down after there had been significant growth, we’re seeing some odd things. This is from the Morton Arb’s Plant Health Care Report:

Black spot of rose is showing up on a number of roses, including ‘Knock Out’ roses, which are normally considered resistant to this disease (remember that resistant does not mean immune). Black spot is caused by the fungus Diplocarpon rosae. Round to irregular black leaf spots with fringed margins appear on either leaf surface but primarily on the upper surface. When infection is severe, the entire leaf will turn yellow and drop. Repeated defoliation will lead to reduction in flower quality and quantity, stunting and weakening of the plant, and increased susceptibility to other diseases.

The fungus overwinters on fallen leaves and diseased canes. Spores are splashed by water or wind-blown rain from fallen leaves and cane lesions to newly emerging leaves and succulent stems in the spring. Warm temperatures, combined with wet leaves and high humidity, will result in abundant spore germination and infection in about one day. Black spots become evident 3 to 16 days later.

Management: Remove infected leaves and canes to reduce inoculum. Plant roses in sunny locations with good air circulation and avoid overhead watering. Avoid planting them too densely. Fungicides should be applied as soon as leaves emerge and continued, at labeled intervals, until leaves drop in the fall. Lengthen spray intervals or skip applications during dry weather.

They offer two good web sites for more information, one from the University of Illinois and the other from the University of Nebraska.

Two people who have been on the front lines during this onslaught are my friends Jennifer Brennan from Chalet in Wilmette and “Dr.” Wally Schmidtke from Pesche’s Garden Center in Des Plaines, another great sponsor of my radio program. Of course, Jennifer is my co-host on our local gardening and cooking TV show, Dig In Chicago, which I assume all of you are tuning in to every Saturday morning at 10am on Comcast Channel 102. Don’t have cable? No problem, you can watch individual segments at and whole episodes at

Jennifer, who appears regularly with Tracy Butler on ABC7 News This Morning, sent me a video from this week’s segment, which includes her Basics for Veggie Gardens and 12 Commandments for Rose Care.

I’m happy to have both Jennifer and Wally on the show this morning to answer some tough gardening questions.