Bulbs are bulbs. Right? Wrong! Many of the landscape plants that we call bulbs are actually something else. Tulips and daffodils are "true" bulbs meaning that they are a type of bud with folded leaves covering the new year's growth. Most of the true bulbs we grow including hardy lilies and Allium for instance are fully hardy for northern climates. They require no special care to make it through the winter other than being properly placed in the soil.

Other plants that we commonly call bulbs such as dahlias, cannas, gladiolus, caladiums, calla lilies and others that bloom in the summer are actually other types of structures. They are technically storage roots, rhizomes or corms and not bulbs.

Many of these types of plants come from tropical or sub-tropical areas of the world where they do not have to deal with winter cold. Therefore, when we grow them in temperate zones of the world where killing frosts and sub-freezing temperatures are routine, they need to be dug up and stored in sheltered locations.

That is why these plants are called "tender" bulbs.

As with other bulb-like plants, the tender bulbs need a well drained soil and will not tolerate poor drainage. For the most part, with the exception of the caladiums, perhaps, they like full sun. These plants tend to need a plentiful supply of moisture and may not due well in droughty situations.

Some summer flowering bulbs can be started indoors under fluorescent lights, but many can be planted outside after the danger of frost is past. Prepare the soil as for other plants. Improve the drainage of heavy soils by working in organic matter.

Planting depths and spacings vary with the individual plants. Check plant tags or other references for specifics.

As always, have the soil tested in the planting sites and follow the recommendations for fertilizer and pH adjustments. Liquid or granular types of fertilizers may be used on these plants.

Keep the soil moist but not waterlogged throughout the growing season. A good guideline is to be sure they get about an inch of water per week in either rain or irrigation.

Tender bulbs are dug when the leaves have turned yellow or the tops have been frosted. Digging times and handling are given under growing instructions for specific bulbs. When digging, make sure the plants are not injured.

Note: We have provided some general information and observations on this topic aimed at the home gardener. Before you take any serious action in your landscape, check with your state's land grant university's Cooperative Extension Service for the most current, appropriate, localized recommendations.