At the diagnostic clinic, Master Gardeners can:

  • Identify plants and weeds.
  • Diagnose common insect, disease or plant problems.
  • Explain how to control pests and weeds with little to no chemical use.
  • Discuss your lawn, tree, flower, vegetable and pest problems.


Wednesday and Saturdays, 11 a.m. - 1 p.m.

June and July
Wednesdays, 11 a.m. - 1 p.m. and 6-8 p.m.
Saturdays. 9 a.m. - 1 p.m.

Wednesdays 11 a.m. - 1 p.m. and 6-8 p.m.
Saturdays. 11 a.m. - 1 p.m.

Wednesdays and Saturdays, 11 a.m. 1 pm.


University of Minnesota Extension Building (The Barn), 2020 White Bear Ave, Maplewood, MN 55109

Bringing samples

  • Collect your sample on the day you come to the clinic to keep it fresh.
  • Fleshy plant parts (bulbs, fruits and roots): wrap plants in paper towels to absorb leaks.
  • Flowers and vegetables: Bring the entire plan with the roots and surrounding soil. Enclose the roots in a plastic bag and keep the soil from touching the leaves. Bring enough plants to show all stages of the symptoms. Note the pattern of symptoms over the whole garden.
  • Foliar disease: Bring enough plants to show all stages of the disease from healthy to sick. Note the overall pattern on the plant (i.e. are all the leaves affected or just the lower branches?).
  • Grass samples: Grass samples must be a minimum of 6"x6" sections with the roots intact. Include sick grass, grass on the edge of the sick area and healthy grass.
  • Woody trees and shrubs: Collect branch samples that show the range of symptoms but are not dead.
  • Insect samples: Bring several specimens if possible. Include plant sample showing insect damage. Preserve soft-bodied speciments in rubbing alcohol.