4. Sprinkling Coffee Grounds Around Acid-Loving Shrubs Lowers The Soil’s pH
Coffee grounds are acidic, and mixing them into the soil can affect pH—slowly. But here’s the catch: Fresh coffee grounds can inhibit plant growth because they tie up nitrogen in the soil as they decompose (just like banana peels), especially if large quantities are added. To lower your soil’s pH without causing a nitrogen deficiency, purchase a sulfur-based soil acidifier (available at garden centers) and amend soil following the package instructions. Many popular shrubs, including azaleas, heathers, rhododendrons, and blueberries, will appreciate soil with more acidity.
5. Adding Fertilizer to The Hole Helps Transplants Establish Faster
No fertilizer, or other soil amendments, on hand? No worries. Adding them to a planting hole isn’t necessary and, in some cases, can actually discourage a vigorous root system. Nutrient-rich planting holes can give roots less incentive to branch out to absorb nutrients and moisture from the surrounding area; and fertilizers, including the phosphorus-rich fertilizers frequently marketed for new transplants, contain salts, which can burn tender new roots if they’re not incorporated into the surrounding soil. If you’re concerned about soil fertility, you’re better off giving plants a nutrient boost by spreading a 1- to 2-inch layer of compost, then 1 to 2 inches of mulch over the planting site. Just be sure to leave a few inches of breathing room around each plant’s stem, especially when mulching trees. Mounding soil or mulch around a tree trunk can cause girdling roots that encircle the trunk and slowly strangle the plant.