Lycium barbarum or Chinese Wolfberry--commonly known as Goji berry--survives winter temperatures down to -15 degrees F and adapts well to rich soil in drier climates. In general, the plant requires much the same care as tomatoes and is even vulnerable to some of the same pests and problems. When mature, the Goji becomes a woody bush about 8 feet tall and 8 feet across, yielding dependable crops of small, sweet red fruit.
Stratify goji seed collected from fresh or dried goji berries by placing the berries in a ziptop bag of clean moist sand and storing the bag in a refrigerator for at least a month. Seed purchased in packets should not need stratification.
Fill 4-inch peat pots with potting mix. Plant stratified goji seeds two or three seeds to a pot and 1/2 inch deep. Plant six to eight weeks before the last frost. Water thoroughly.
Place the peat pots on a tray near a south-facing window. Keep the pots moist and warm but don't set them in direct sunlight. First seedlings emerge in about two weeks.
Thin to a single goji seedling in each pot when the most vigorous plant grows its second set of leaves. Place the seedlings on a warm windowsill for the first few weeks of growth. Windows facing south give new plants a few good hours of sun and natural warmth daily.
Harden off the goji plants after the last frost of the spring by taking them outside briefly during the day and exposing them gradually to longer periods of outdoor temperatures. Hardening off should take about two weeks. Direct sunlight could kill young goji plants--set plants in dappled shade until they fully adjust.
Plant goji in nursery rows spaced 2 feet apart. Protect young plants from variable spring weather with covers cut from empty plastic milk or water jugs. Transplant to permanent locations in the fall after plants go dormant for the winter.