Don’t plant perennial herbs before last frost

By Lelia Kelly and David Nagel
MSU Horticulture Specialists

In some areas, you’ll already find transplants of perennial herbs, such as thyme, lemon balm, oregano, chives and winter savory at your garden center.

Although some of theseherbs tolerate frost, the transplants are probably fresh from a greenhouse. Wait until the threat of frost has passed, and plant them in a location with good drainage and at least a half-day of sun.

Fruit Trees

When purchasing fruit trees for the home orchard be sure you understand the pollination requirements for good fruit set. Some trees are self-pollinated, some not and others, even though considered self-pollinated, benefit from cross-pollination for good fruit set.

Sometimes the plant labels indicate the variety that is recommended as a pollinator —most of the time it does not. So, if you are uncertain, be sure to ask the nurseryman or call the Extension office for this information. Some general guidelines follow:

Most apple and pear varieties require cross-pollination from another variety planted within one-fourth mile of one another. “Honeysweet” pear and “Hosui” Asian pear are self-pollinating. Pie or tart cherries (“Montmorency”) are self-pollinating and do not require another variety to set fruit. Peach and nectarine trees are self-pollinating but will set a heavier crop of fruit if cross- pollinated with another variety planted within a quarter mile.

Most Japanese plum varieties require pollination from another variety planted within one-fourth mile. Examples of Japanese plum varieties are “Methley” and “Shiro.” Most European plums (“Damson,” “Green Gage”) are self-pollinating.

Pruning

Sap has begun to rise in many landscape plants. Observe buds on woody ornamentals and be prepared for dripping sap if the buds have swollen before you prune. Roses are probably still safe to prune.

Vegetables

Plants are available in garden centers. Remember that warm-season crops like peppers, tomatoes, sweet corn and beans are not freeze tolerant. Be prepared to cover these plants when the cold fronts blow through.

Often covering with a sheet of plastic or an old bed sheet is sufficient to get the plants through one night of below-freezing temperatures. There is still time to plant cool-season crops. If your crop was killed by low temperatures, plow the dead material in and replant.

One interesting plant to try is salsify. This is one of those plants that was popular 200 years ago, but the long growing season and the availability of real oysters far from the saltwater made it just about disappear from home gardens.

These are planted in early spring (now for some of us) but are not harvested until fall. The plant is like a turnip in that you can eat both the leaves and the root. The leaf bases are eaten like greens and the root is similar in shape to a carrot. One of salsify’s nicknames is oyster plant and some gardeners claim it has an oyster flavor. Other gardeners claim it tastes like artichoke.