For a beautiful spring display, you should plan to plant bulbs in fall. Now is the time to think about what bulbs you want to plant.

Given the array of variety, size, color and bloom-time, bulbs add a significant return on financial and time investment to any home garden and landscape.

The term bulb is associated with a family of perennial plants formally called herbaceous geophytes. Bulbs store nourishment for the plant’s life cycle during dormant periods when the weather is either too cold or too hot for them to flower.

The major types of bulbs include true bulbs (daffodils and tulips), corms (crocus), tuberous roots (dahlias), rhizomes (iris) and stem tubers (potato).

Spring-blooming bulbs are planted in the fall, before the first frost, for an early to late spring or early summer bloom. Summer bulbs are planted in the late spring after the last frost, typically May 31, for summer- to early-fall blooms. Summer bulbs are dug up and stored over the winter as they are not winter-hardy like spring bulbs.

Plant bulbs with attention to their site location and preparation, soil characteristics and planting depth. Site selection and preparation are key to many years of successful bulb growth and flower production. Select a site that accentuates the bulbs’ best features, such as their size, color and bloom time.

Bulbs prefer full sun. Planting spring bulbs under deciduous trees takes advantage of the sunlight before the trees leaf out. Excellent soil drainage is crucial for root development and bulb rot prevention during the dormant season.

Conduct a soil test to measure soil pH and nutrients, and amend the soil based on the test’s recommendations. Bulbs prefer a soil pH between 6 and 7. Introducing organic matter, such as compost, helps stimulate and support root development in a clay soil.

Create a design that incorporates bulbs into your existing spring and summer garden beds. A solid wave or drift of flowers provides more impact from a distance as compared to a small mixture of colors and varieties.

Learn about the bulbs’ bloom time, size and color to contrast and complement spring perennials, shrubs and trees. In general, keep kinds and colors of bulbs together. Tall bulbs should be planted near the rear of your selected site or garden with shorter bulbs planted toward the front.

Purchase high-quality bulbs from a reputable grower. Quality bulbs are typically larger and free from cuts or gashes. Healthy bulbs should feel firm to the touch. Bulbs are typically planted two-and-one-half to three times deeper than the bulb height.

For example, a tulip bulb that is two-inches-long should be planted at a depth of five or six inches. Follow the recommended planting directions on the bulbs’ packaging. Dig the bulb bed to the proper depth and press bulbs into the soil with the pointed end up and the root base down. Cover with soil and approximately two to three inches of mulch. The mulch protects the bulbs during winter by minimizing temperature fluctuations while maintaining soil moisture.

In the Lehigh Valley, the best time to plant bulbs is September to late October, before the first frost of the season. Bulbs will have time to develop a solid root system before the ground freezes.

Once planting is complete, be patient and wait for spring. As the spring days gradually become warmer and longer, the long-awaited display of color emerges.

After blooming, keep the green foliage on the bulb, which provides the bulb much needed nutrients for next year’s blooming season. Water the bulbs whenever the soil is dry.

If bulbs are going to be maintained in the same planting bed year after year, fertilize with a bulb-specific fertilizer. Divide bulbs when they become crowded, overgrown or not flowering. Spring bulbs can remain in the ground year-round.

The gorgeous shapes, varieties and colors of spring bulbs make even the overcast and damp spring tolerable. As we enjoy fall harvests, think about how wonderful next year’s spring blooms will be in your garden. Invest in your garden’s spring splendor by planting favorite or new bulbs in fall.

“Growing Green” is contributed by Lehigh County Extension Office Staff and Master Gardeners. Information: Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-813-6613.