Wintergreen (Teaberry)

Set plants where they get dappled or partial shade and the soil is moist, well drained, and high in organic matter. Test pH before you plant and aim for 4.5 to 6.0; wintergreen tops out around pH 7.0 and will sulk above it. The plant survives deep shade, but site it where some light reaches the ground if you want berries rather than just foliage. This is an ericaceous woodland understory plant adapted to acidic, humus-rich forest soils, and while the evergreen mat persists in heavy shade, fruiting usually happens in canopy openings where more light gets through.

Keep the soil evenly moist but never waterlogged through the first couple of growing seasons, particularly in dry spells. Once the mat has spread and closed, ease off - established plants handle occasional dryness on their own. Wintergreen wants moist but well-drained ground, and its rhizomes sit in the shallow organic layer that dries out first, so a young planting has almost no reserve to draw on.

Glance over the leaves a few times through the season for aphids, thrips, powdery mildew, and leaf spot. All four are occasional and cosmetic here. Knock aphids off with a hose and open up air movement rather than reaching for a spray. Wintergreen has no serious pest or disease problems, so the damage almost never justifies an intervention, and a groundcover worked by bees is worth more intact than sprayed.

The red berries color up after the summer bloom and hang on the plant through winter, sometimes into the following spring, so pick at your leisure once they are fully red rather than racing a window. Take leaves a few at a time from scattered stems instead of stripping any one plant. The fruit is persistent rather than perishable, so there is no narrow picking window; the leaves, by contrast, are evergreen and are the plant's only photosynthetic tissue through winter, so heavy stripping sets the colony back.

Top up with a thin layer of leaf litter, pine needles, or other acidic organic matter as the leaves come down, and leave fallen leaves in place over the patch. Keep it loose and shallow. Never till, dig, or hard-rake an established colony. The rhizomes that carry the whole colony run in only the top inch of the organic layer, so stripping the litter or cultivating the surface destroys the exact tissue the plant spreads from.