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Unearth the Magic of Your Garden: A Detailed Guide to Bulbs, Corms, Rhizomes, and Tubers

July 20, 2023

All about bulbs

The secret to many stunning gardens lies hidden beneath the surface, in the miraculous world of bulbs, corms, rhizomes, and tubers. These botanical powerhouses, full of energy and nutrients, make the miracle of each new season possible, and understanding their needs and lifecycle is key to a successful garden.

Bulbs – Nature’s Self-Contained Plants

Bulbs are nature’s perfect survival package. Storing nutrients during adverse weather conditions, they help plants navigate through their lifecycle, guaranteeing a vibrant display year after year.

True Bulbs– Packed into this compact structure are entire plants. Common examples include daffodils, tulips, and hyacinths. These bulbs produce new stems from their base and often create smaller ‘bulblets’ that can be separated and planted individually.

Corms– Species such as the crocus, freesia, and gladiolus originate from corms, which are essentially nutrient-storing stem structures. These parent corms produce cormels or baby corms, which can develop into new plants.

Tubers– Think of dahlias or certain begonias. They form tubers, nutrient-filled underground roots or stems.

Rhizomes– A classic example is the iris. Rhizomes are specialized stems that grow horizontally, just below or along the surface of the soil.

Spring Bulbs vs. Summer Bulbs

Spring Bulbs Winter-hardy, spring bulbs like hyacinths, tulips, and daffodils are planted in the fall. They reward you with a splendid display in spring, before entering a dormant phase. Unless overcrowded, these bulbs can usually remain in the ground year-round.

Summer Bulbs Dahlias, cannas, and gladioli are examples of summer bulbs. Planted in spring, they flower throughout summer and require lifting and storing over winter in colder climates.

Essential Practices for Bulb Planting

Whether you’re a fan of sun-loving or shade-loving bulbs, good soil preparation is essential. Bulbs usually prefer a soil pH between 6 and 7. Adding organic material can drastically improve drainage in clay-heavy soil.

When it comes to planting, depth is crucial. After placing the bulb (typically pointed end up), cover it with soil. A layer of mulch can be beneficial in regulating temperature and maintaining moisture. A good soaking immediately after planting helps settle the soil and encourages root development.

Master Gardener Tip: Using a bulb planter can make planting bulbs and the like simple, and efficient.

Maintaining Healthy Bulbs

After flowering, allow the bulb leaves to naturally wither and brown. These leaves are vital for photosynthesis, producing the nutrients required for the next growing cycle. Once the leaves are dried up, spring bulbs can stay put or be lifted for fall replanting, while summer bulbs should be stored over winter.

Dividing and Replanting for Bulb Rejuvenation

Over time, bulbs may become overcrowded or show a decline in flowering. If this happens, it’s time to lift or divide them. After the foliage has yellowed, gently lift the bulb, detach the bulblets, and replant.

Top Tips for Thriving Bulbs

  1. Maintain regular watering during the growing season.
  2. Weed frequently to prevent competition for nutrients.
  3. Apply fertilizer periodically throughout the season.
  4. Scatter groups of daffodils for a natural, picturesque garden.
  5. Use strategic planting to disguise wilting foliage behind other plants or pair with ground covers or perennials.

By understanding the unique requirements and lifecycles of bulbs, corms, rhizomes, and tubers, you can elevate your gardening game, ensuring a beautiful and flourishing garden all year round.


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