Rick Durham, Consumer Horticulture Extension Specialist, University of Kentucky
 

Daffodil care after winter damage.

Did the late winter cold do a number on your daffodils this year? For those that were fairly tall when the cold weather hit, the flower stalk and some of the leaves fell over to the ground after the severe freeze. Those that were still short and protected by soil or mulch were affected very little. This is because the base of the leaves and flower stalk is the site of active cell division and growth, the part of the plant most susceptible to severe cold. What should be done to promote healthy growth and blooming next year?

First, dead foliage or flowers should be removed, but don't cut the live foliage back until it naturally turns yellow. This will give the plant opportunity to replace some of the energy used during flowering and help ensure a good show of blooms next year.

Second, make sure plants are well watered while the foliage is still green. Natural rainfall is usually sufficient for bulbs, but supplemental water may be needed during times of drought.

If you want to dig and divide daffodils, the dormant season or late summer is considered the best time. Dividing crowded clumps will invigorate the plants and promote increased bloom in future years.
 

Are Heirloom Vegetables in your Future?

Have you visited your local farmers' market lately? If so, you've probably encountered some heirloom vegetables. Or if you're into vegetable gardening yourself, you've probably noticed more and more heirloom vegetable varieties being marketed by seed companies. One popular TV home and garden personality even has her own line of heirloom vegetables that are marketed through a local discount department store. So why all the hype?

Heirloom varieties are usually older cultivars that were developed in the early 1900's or before. Many current heirlooms were popular in the World War II victory gardens, others were introduced from overseas by immigrants over the past few hundred years. Still others have their origin in Native American culture. One thing that sets heirlooms apart from modern cultivars is that heirlooms are not hybrids. Rather they are called open pollinated, meaning that they are allowed to cross hybridize with one another and they usually come true-to-type in the next generation. Unusual seedlings that arise during the next generation are eliminated, unless they look promising themselves. If the unusual seedling shows merit, it may be propagated, further evaluated, and designated as a new variety.

Home and commercial gardeners and seed companies often partner to maintain heirloom varieties. One of the largest and most extensive partnership of this sort is the Seed Savers Exchange of Decorah Iowa. Seed Savers has over 8,000 members who grow and distribute heirloom varieties of vegetables, fruits, and grains. A similar but separate organization, the Flower and Herb Exchange promotes the preservation and propagation of heirloom herbs and flower varieties. Many commercial seed companies also maintain and market heirloom varieties.

So what makes heirloom vegetables special? Many people believe such varieties have superior flavor since they have been selected for taste and tenderness over many generations. This is in contrast to many modern cultivars that have been selected for ease of shipping, firmness, appearance, and country-wide adaptation to climate. When heirloom varieties are maintained by a particular family or group of people, they tend to become adapted to local climate and soil conditions and may even become more pest resistant. Some people just enjoy being involved in the process of regenerating plant varieties year after year.

Here are some of the more popular heirloom varieties that are fairly easy to find in the seed trade. Golden Bantam sweet corn, Brandywine tomato, Lemon cucumber, Kentucky Wonder pole bean, Golden Hubbard squash, and Moon and Stars watermelon, to name a few. Some of these varieties may be more susceptible to disease than modern hybrids, but with a little extra care, they will reward with flavorful produce for the table and pantry. So try some heirloom vegetables for a bit of history and a lot of flavor.
 

Pawpaws for late summer fruit.

We hear a lot about pawpaws in Kentucky. They are a native fruit tree that many of us remember from exploring the woods in our youth. Researchers at Kentucky State University and the University of Kentucky have been conducting research with pawpaw for several years. Kentucky State University serves as the National Germplasm Repository for pawpaw, meaning that a large collection of pawpaw varieties are grown and maintained there. This allows researchers to evaluate these varieties to see which produce the best fruit. Other research is aimed at determining what cultural practices are best for pawpaw production and how best to store and process the fruit.

Pawpaws are a great addition to the home landscape. They are a small tree that grows to about 15 or 20 feet. They also can be grown under a variety of conditions, from full sun to fairly heavy shade. Young plants will need to be grown in partial shade for the first year or so. This can be accomplished by planting in a shady area or erecting a temporary shade structure. Best fruit production will occur on plants grown in full sun but plants will also produce a few fruit when grown in the shade. Stay away from wet sites, pawpaws prefer soils that are well drained. If your soils are heavy with clay or compacted, you will need to loosen the soil by cultivation and incorporate some organic matter such as leaf mold or compost before planting.

For fruit production, you will need to plant at least two varieties since pawpaws are not self fruitful. Although the flowers are pollinated by flies and beetles, you may have more fruit if you practice hand pollination. Use a small artist brush to move pollen from one variety to the flowers of another. This can be a great family project. Pollen is ready when the anthers are brown and release yellow dust-like pollen. The flower stigmas are ready to receive pollen when their tips are green and glossy and their anthers have not yet opened. Fruit will ripen from mid August to October, depending on the variety.

Pawpaw is a fruit crop that requires very little pruning except to remove damaged or dead branches, or to correct unwanted growth. Occasional pruning of older trees will encourage new growth and better fruit production. Pawpaws also have few pest problems.

Named varieties will produce better quality fruit than seedlings. Consult local or mail order nurseries to determine what varieties are available. Some varieties recommended for Kentucky include Davis, Prolific, Sunflower, Sweet Alice, and Wells, to name a few.
 

Nick seeds to promote germination.

Seeds must absorb water to germinate. This may seem trivial, but some seeds have a difficult time accomplishing this simple feat. The seed coat or covering may be very thick and resist the uptake of water. This thick seed coat protects the seed and In nature the seed coat is acted upon by microbes in the soil where it is gradually degraded over time. Some such seed may be ready to germinate in a year or so, while others may lie dormant for several years before germinating. This ensures that there will be seeds available in the soil for several years in case weather conditions do not favor a new crop of seeds. Other seeds may become able to germinate after they pass through an animal's digestive system. The acids in the animals stomach act on the seed coat to make it more permeable to water.

What does all this mean for the home gardener? Occasionally on seed packets there will be instructions that call for nicking the seed before planting it. The technical term for this is scarification. The seed will germinate only poorly if not scarified in some way. If seeds are large they may be scarified by nicking the seed with scissors or pruning shears. Simply make a shallow cut into the seed. If a lot of seed need to be treated, or the seed is small, try rubbing the seed several times between two pieces of sand paper. Commercial seed companies often soak such seed in acid before germinating. This is not recommended for he homeowner since the acids used are very strong.
 

Other things to do in March and April.

• Check lawnmowers and other power landscape and garden equipment to ensure they are in good working order. Arrange for repair and routine maintenance early to avoid the crowds later in the season.
• March is usually an excellent time to prune woody plants in the landscape. The best time for pruning most plants is just before growth begins in the spring. An exception is spring flowering plants that should be pruned just after flowering.
• Pull back mulch as perennial resume growth in the spring. A heavy layer of mulch may help to protect plants through the winter, but may suffocate young shoots as growth resumes in the spring.
• Sow seeds of cool weather crops. Radishes, onions, lettuce, and spinach should be the first ones planted followed by beets, turnips, carrots, Swiss chard, and peas. Also, transplant broccoli, cabbage, and other cole crops to the garden now.
• Treat lawns with pre-emergence herbicide for crab grass control. The ideal time to treat is when the bright yellow flowers of the forsythia shrub are evident.