Southwest Michigan vegetable regional report – July 15, 2015

Sunshine and warm temperatures would be welcome.

Weather

Temperatures over the past week continued their up and down pattern with highs from 69 to 86 degrees Fahrenheit and lows from 52 to 67 F. The area received 1 to over 3 inches of rain. Most rain came in a short time Monday, July 13, causing flooding and erosion in many fields. We are near 1,290 base 50 growing degree days (GDD) compared to 1,265 GDD for 2014.

Excessive rains across much of the area have caused nutrient leaching in many fields with the primary symptom being yellowing plants in the sandier areas. Nutrients most prone to leaching are nitrate nitrogen, boron, sulfur, chlorine and molybdenum (see table). For the full article on soil nutrient mobility, go to “Anions and cations in plants, oh my! But why do we care?

Crop reports

Michigan State University Extension has reported downy mildew is close to the area, so cucurbit growers are encouraged to decrease spray intervals to four to seven days, especially during periods of cloudy, cool, windy, wet weather, which continues to describe our season so far.

Sweet corn harvest for local sales has begun.

Watermelon and pumpkins are in bloom.

Tomato and pepper harvest is expected to begin next week.

We have not seen much activity to date for European corn borers, corn earworms, squash vine borers or squash bugs.

Soil-borne elements essential for plant growth, the form occurring in the soil and taken up by the plant, and their relative soil mobility

Element (symbol)

Form taken up by plant

Mobility in the soil

Nitrogen (N)

(NH4)+ Ammonium form

(NO3)- Nitrate form

Somewhat immobile

Mobile

Phosphorous (P)

(H2PO4)-, (HPO4)-2, PO-3

Immobile

Potassium (K)

K+

Somewhat mobile

Calcium (Ca)

Ca+

Somewhat mobile

Magnesium (Mg)

Mg+2

Somewhat mobile

Sulfur (S)

(SO4)-2

Mobile

Chlorine (Cl)

Cl-

Mobile

Iron (Fe)

Fe+2

Immobile

Boron (B)

(BO3)-

Mobile

Manganese (Mn)

Mn+2

Immobile

Zinc (Z)

Zn+2

Immobile

Molybdenum (Mo)

(MoO4)-

Mobile

Related Articles

Related Resources