Deadheading means pinching or cutting back old flowers to encourage continuous bloom. Cut down the entire bloom stalk of perennials, such as salvia, yarrow, penstemon, and delphinium. Mounding perennials, such as brunnera, nepeta (catmint), lamium, and hardy geranium, can be cut to the ground to stimulate new foliage and possible re-bloom. Other perennials that usually re-bloom after deadheading are: Centranthus (valerian), Matricaria (feverfew), tiarella (foamflower), gypsophila (baby's breath), and most phlox. Fertilize after deadheading.
Mulch is a material laid on the soil around plants to maintain even soil moisture and temperature levels and to minimize weeds. Mulches may be inorganic, such as rocks, pebbles, or weed barrier fabric, or organic, such as shredded wood chips. Rocks do not block weeds well. They tend to heat up the soil and absorb reflected heat from adjacent buildings; excessive soil heat is detrimental to tree and shrub roots. Organic mulches add nutrients to the soil, but need to be replenished over time. For permanent beds around trees, shrubs, and perennials, use a three or four-inch layer of mulch. Christmas tree branches, hay, or straw may be used for temporary winter mulch.
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