Yarrow and Summer Phlox help
Posted by KimmSr from MI-4a/5b on 2008-11-01 09:15:00

My 2nd summer with a perennial garden. It's in full sun (8 hrs) with a few inches of cedar mulch. Everything survived 2007's brutal drought & no watering mandates. But the Yarrow is short, blooms white then turns brown. Most of the stems then brown and die out quickly. They seems to like the warm Fall & have bloomed again after little this Summer. Is it too much sun? And the Summer Phlox barely blooms. Many stems came up about 2' with buds then never bloomed. The stems are very thin & week. Guess they needs staked, but I thought they had much thicker, stronger stems. I fertile with Miracle Grow in Spring every other week. Then 1x per month in summer. What else can/should I do?

You need to contact your South Carolina State University USDA Cooperative Extension Service local office about having a good, reliable soil test done as well as dig in to see what needs to be done to make that soil good and healthy. These simple soil tests can help you,
1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

What I have sen over the years is that Yarrow seems to prefer a leaner, meaner soil than does garden Phlox. My Yarrow has migrated to places where the soil is not nearly average.