1. Mulches for Landscapes Bob Neier Sedgwick County Extension Agent, Horticulture

2. Mulching Benefits: –Improves plant growth –Maintains moisture –Maintains temperature –Inhibits weed growth Organic mulch decomposes and adds nutrients and organic matter to soils

3. Mulch Organic Mulches –Leaves/leaf mold –Wheat Straw –Pine Straw –Grass clippings –Shredded bark or wood waste

4. Mulch Inorganic Mulches –Rock, gravel, rubber, fabric Does not provide the soil benefits of organic mulch Rock can increase soil temperature as it absorbs heat Light-colored rock may reflect heat onto plants

5. Woodchip Mulches Garden centers Arborists/Tree Care Companies Christmastree Recycling

6. Woodchip Mulches -Increases growth rate of trees & shrubs vs. grass up to trunk -3” from trunk -2-4” deep -5-6’ diameter -Shredded branches or bark chips work great

7. Close mulching may bring – girdling roots

8. Benefits of Mulches Conserving water by slowing down evaporation Smothering unwanted plants and inhibiting their growth Insulating the soil, thereby moderating the fluctuation of soil temperature to protect the roots and stems of plants Prevents crusting of the soil surface and increases water infiltration Reduces compaction Neat & attractive

9. Surface insulation –to conserve moisture –to moderate extremes in temperature –to control weeds Beautification –to make surface areas more attractive –to make surface areas more usable for paths, play and sitting areas –to make areas easier to maintain

11. Cooling Effects of Mulches (Dr. Curtis Swift, Colorado State University Extension 8-13-03) Compared –Bare ground –Rubber mulch –Mini Bark –Pallet Mulch –Cedar Mulch Results –Ambient air temp 98.2 o –Soil temps at 1 ½ inches Bare soil – 101.6 o Under Mulches – 83-89 o

12. Rubber Mulches Weed Control – not as effective as organic mulches Flammable – highly & difficult to extinguish Permanent? – like other organic mulches, it decomposes Non-toxic? Leachates can be toxic to aquatics and plant roots –Dr. Linda Chalker-Scott, Ph.D, Extension Horticulturist, Washington State University

13. What mulch to use Woodchips Bark Cottonseed Hulls Straw Grass Clippings Newspaper Cocoa bean Pecan Shells Salt marsh hay Prairie hay Compost Pine Straw Sawdust Leaves Plastic Rock Rubber

14. Single Season Mulches Grass Clippings Leaves Compost Shredded paper Peat moss Straw Corn stalks Ornamental Grasses (chopped)

15. Composts/Leaf Mulches May be worked into annual beds or as a surface mulch Increase Organic Matter Content Improve drainage Reduce root diseases Cools soil 5-15 º F

16. Persistent Mulches Bark Chips Woodchips Pecan hulls Pine straw Sawdust Cottonseed Hulls

17. Inorganic Mulches Weed barrier fabric Plastic Rock Gravel

18. Fabric mulches Used in Kansas field windbreaks No additional water needed on young trees

19. How much to use 2-4 inch layer of most products needed to: –Insulate soil effectively –Prevent weed growth

20. Fabric under mulches Use landscape fabrics under organic mulches for additional weed protection –Can reduce organic mulch to 2” with the use of fabric below

21. Trees & Shrubs Important for young trees for root establishment Use 2 bags /tree Keeps equipment from trunks on older trees

22. Wood/bark Mulches for Trees 2-3 inches deep 3 ft from trunk to drip line Keep 3-6 inches from trunk Keeps summer temperature 5-15ºF cooler

23. Fruit Trees Mulch fruit trees to drip line

24. Broadleaf Evergreens Mulches reduce winter scorching of broadleaf evergreens –Mulches keep the soil moist –Plants can scorch in frozen soil –Mulch beyond edge of plants

25. Roses Use coarse materials, 3” deep Mound compost or soil 8” over center of plant after ground has frozen in December

26. Flower & Vegetable Gardens Prevents erosion Use finer textured mulches –They may be worked in at end of season Do not work in wood chips –They tie up nitrogen when worked in

27. Perennials & Strawberries Winter mulches (straw/pine needles) prevent frost heaving of crown Mulch after soil has frozen

28. Mulchmowing Remove 1/3 or less of blade Recycles nutrients to the soil Organisms in the soil break down clippings Does not contribute to thatch

29. Surprises in mulches

30. Problems with mulches Sawdust mats and reduces water infiltration Wheat in straw Grass clippings slimy Blowing of paper mulches Mold/fungi in woodchips

31. Moldy Mulch? Use pitchfork to loosen mulch to increase aeration

32. Improved Aesthetics Beds Pathways

33. Rings tell the story Which side of this tree –Had better growing conditions? –Had less soil compaction? –Easier root growth

34. Makes mowing easier Mowing is easier/faster Keeps mowers away from plants – less plant damage

35. Prevent Weed Trimmer Injury use mulches

36. Protect Water Quality Largest Pollutant in Rivers Sediment Other potential pollutants – –Fecal bacteria –Nitrogen –Phosphorus –Pesticides

37. Protecting Water Quality Prevent erosion Tree planting along water flow banks Unmowed grasses filter Don’t fertilize near water Apply Phosphorus according to soil test needs Sweep/blow fertilizers from streets & walks

38. By Bob Neier County Extension Agent, Horticulture Sedgwick County February 10, 2010