SOILS, MULCH AND AMENDMENTS Photo Credits: free-graphic.com photobucket.com

IT ALL STARTS HERE Over 80 percent of plant problems begin with the soil You and I have many choices for our nutritional needs Plant have to depend on what is in the soil where they are planted.

GOOD SOILS Ideal is loam, nearly equal mix of sand, silt and clay with living organisms. – 45% mineral, 25% water,25% air, 5% organic matter Texture, structure and fertility determine soil’s ability to support plant growth.

TEXTURE Texture – size and proportion of particles in soil Sandy – larger, gritty, falls apart Drains off water & nutrients quickly Clay, smallest – sticky – gummy holds water & nutrients Silt – smooth – floury – fertile There are some of the above in all soils.

STRUCTURE Arrangement of soil particles How individual particles clump or bind together Arrangement of soil pores and paths between Affects root growth, seedling emergence, movement of air and water Compaction affects structure

COMPACTION Can cut crop yields by 50% reduced aeration resistance to root penetration poor drainage Caused by construction machinery, vehicles, footsteps, pounding rain

FERTILITY Ability to supply nutrients to support plant life and growth. – Nitrogen (leaf growth), phosphorus, potassium – Minerals in a form that can be taken up by plant – Organic matter and microorganisms – Hold water long enough for plant to absorb it – Drains water off in a reasonably short time – Contains oxygen

pH Best for plant growth 5.5 to 7.5 Most Colorado soils are 7.0 to 8.3 Rainfall effects the pH Big problem is iron chlorosis – Chelated iron Acid soils can be raised with lime Not much will lower pH– Acid loving plants struggle – Rhododendrons – Azaleas – Blueberries – Heather – Lily of Valley

OUR SOILS Most of the soil in our area is hard clay, alkaline, dry and compacted. – Lacks organic matter – Lacks oxygen – Drains slowly – Periodic droughts

AMENDMENTS – Improves structure – heavy clay, letting in oxygen – sandy soil adds substance – Compost – homemade best – Aged manure – Sphagnum peat – renewable and acidic – Vermiculite – naturally occurring mineral – Perlite – naturally occurring siliceous volcanic rock – Worm castings – Coir - shredded coconut husks compacted – Cover crops – Good quality top soil can be beneficial – flower beds, vegetable gardens – not trees or native plants

APPLICATION One inch annually – manure and castings Two-three inches annually – compost, peat, vermiculate, perlite, coir Dig into the top 6 to 8 inches of soil. After 3 years reduce the amount of amendments If using manure or bagged compost, know that salt can build up in your soil, making it more saline. Use them cautiously. Home made compost is better

FERTILIZERS Nitrogen – Phosphate – Potash - trace minerals – Given as ratios – equal amounts – (Nitrogen 20, Phosphate 10, Potash – 5) ORGANIC – Fish emulsion – varies – – Seaweed – varies – – Bone Meal – often Bulbs like high phosphate – Blood Meal – common Too much nitrogen results in growth of foliage at the expense of flowers/fruit

MULCH Covering soil – Holds in moisture – Cuts water usage – Helps control weeds – Protects root from winter damage and summer heat – Can improve soil - organic – Can provide nutrients - organic – Encourages earthworms - organic – Gives a finished look to garden

ORGANIC MULCHES ORGANIC MULCHES Wood chips (wind) Straw & hay (wind) Grass clippings 2 inches (mat) Leaf mold Pine needles Cedar shreds Many regional products Keep back from trunk/stem

INORGANIC MULCH Inorganic mulch does not break down, not enrich soil, can be hot - DOES NOT BLOW Don’t use in vegetable garden or woodland plants Pebbles Pea gravel Crushed gravel Small rock Rubber/glass (ground) Landscape fabric AS A RULE, DO NOT USE PLASTIC AS MULCH

What ABOUT THE HEAT POTENTIAL WITH INORGANIC MULCHES? Plain rock mulch will be hot in summer and will look hot Plant in the mulch – will look much cooler and be cooler

WHAT ABOUT PLASTIC? Black plastic warms soil – sweet potatoes, tomatoes and peppers Remove at end of season Red plastic to increase yield of tomatoes/other vegetable Newspaper, well anchored – no colored inserts Clear plastic used to kill weeds, viruses – also kills microorganisms, earthworms, sterilizes soil

FIXING YOUR SOIL SOIL TESTING INFORMATION IN YOUR BOOK FERTILIZE BASED ON WHAT IS LACKING ADD ORGANIC MATTER – 2 INCHES INTO THE TOP 6 TO 8 INCHES OF SOIL MIX IN WELL WITH EXISTING SOIL REPEAT ANNUALLY FOR 3 YEARS, THEN REDUCE AMOUNT BUT KEEP ADDING