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Getting Things Ready for a Beautiful Flower Border

soil preparation, grit for plant bedsProfessional landscapers start every flower bed by building superb soil structure—at least the ones who make money do! A flower bed without the right components is like a cake without flour. The preparation starts with a soil test. The result is a handy list of essential ingredients for your best-blooms-ever recipe. Take a paper bag full of the typical existing soil down to your local extension office for analysis. The cost is usually just a few dollars.

Now I’m going to say something you may not like—I know you aren’t going to get a soil test. Almost no one does, even if they are required to do it in the contract specifications! I can give you no logical reason for this, except an unnatural phobia for agriculture extension agents. Anyway, I will repeat it. Professional landscapers who are successful in their business have their soil tested before digging in. You can’t change the weather or control which pests and diseases that visit your site, but you can modify the soil. The sites with the pretty flowers make the time to test.

Soil preparation should be done in late fall after all the flowers are spent and the herbaceous foliage has turned to straw. Fall is the best time to add lime, too. Lime needs several months to affect the soil pH/acidity. As plants suck nutrients out of the ground they tend to lower the pH, and a yearly lime addition provides the buffer to bring it back up to non-toxic levels.

Why don’t you wait until the spring to prepare the soil? In spring, the ground is saturated with winter rains. Stirring up soggy soil particles destroys their structure, but if you wait until the ground has dried out and is ready for tilling, you will have missed the best moments for use of the spring, rain-soaked, moisture-laden ground into which new plants love to grow their roots. Take care of the soil preparation while the weather permits in the fall so you can delicately insert new plants in the ground without disturbing the soil structure in the spring.

A virgin plot of soil can’t be simply tilled to loosen the base for adding amendments. That’s a good way to break a tiller! Hardened soil requires more drastic action. Home gardeners can break up heavy soil by double digging by hand. Better yet, pay someone to do this difficult task for you using a garden fork. Professional landscape companies attach a ripper to their tractor to break through the crust and rocky soil. Lazy gardeners will find that stopping soil preparation activities and trying to plant at this point will cause the ground to quickly revert to its original condition. You have to add more ingredients to make your soil useable.

Clay holds moisture and nutrients, but it turns to hard pottery if you don’t add sand and organic matter. They expose the clay particles to essential air and water. You will need to add organic matter every year, since it decays and gets used up. Adding amendments permanently prevents the top foot or more or soil from morphing back into a hard shell after a rain.

Add manure and composted leaves with lime and grit, and then till the newly ripped soil. Use as much lime as the soil test recommends, and add about a two-inch layer of grit. Then incorporate as much organic matter into the soil as you can afford. Creating an ideal loam (that’s the term for perfect soil) is expensive and labor-intensive. The cost is too high for regular woody shrub beds. Herbaceous plants needs a little extra love, though. You should end up, after all your generous attention, with a fluffy, eighteen-inch-deep bed.

Sand or the even better component, grit, is there to loosen the structure of clay so it doesn’t form hard clods. It only needs to be added once. Grit is great! It makes tilling easier and saves you from ever having to do the back-breaking task of busting clods again. Use fine-textured gravel or coarse-textured sand. Quarries might label grit as “eight-nines” or “eight-tens”, indicating the size of the sieves they use.

Top off the bed with a three-inch layer of organic mulch or a winter cover crop. Your flower bed is perfect and ready for new plants! 

Flower Beds Need Special Soil Preparation