Here are some tips for purchasing your bulbs. The size of the bulb is directly correlated to the size of the flower, and the bigger the bulb, the bigger the flower. Look for healthy bulbs, avoiding any with mechanical damage or mold. You may also want to purchase a bulb digger, soil amendment, and fertilizer.

Site Selection:

Most bulbs prefer a full sun environment and well-drained soil. You may want to mix your bulbs in with other perennials so that when the bulbs are done blooming the perennials will follow and conceal the dying foliage of the bulbs. Also consider early, middle, and late spring blooming bulbs so you have color going at all times. Usually, planting one color in mass is more effective than mixing colors throughout your bed. Be careful of plantings on the south side of the house, especially those near the foundation; sometimes the extra heat generated can induce earlier blooming and cause frost damage to your bulbs.

When to plant:

The best time of year to plant in Central Oregon is the end of September through October. You want to make sure the bulbs become well rooted (allow 2-3 weeks) before the ground freezes.

Preparing the site:

Bulbs are planted at various depths dependent upon the species (see chart below). As a general rule of thumb, bulbs should be planted 4-5 times the height of the bulb between the tip of the bulb and top of the soil (see figure below). Be sure to plant the growing tip (pointy side) up. You will want to add organic matter (1/3 – ½) to the native soil that you remove when you dig the hole for your bulbs. If possible, excavate the bed to the level at which the bulbs are to be planted. Add the soil amendment and fertilizer (super phosphate) to the bed at this time, and rototill to a depth of 3-4 inches. If you are unable to excavate then dig the holes individually and amend them with soil and fertilizer at the appropriate depth. Phosphorous fertilizer does not move through the soil and therefore needs to be applied at the time of planting so that it is available to the roots. Water in well. Once the ground is frozen, you should cover the bulbs with approximately three inches of mulch to prevent the bulbs from freezing and thawing.

Follow up care:

Once your flowers begin to wither, you’ll want to cut them off, otherwise seed production will occur taking some of the food source away from the bulbs for next year. However you do want to allow the foliage to die back naturally, because it uses sunlight to produce food to be stored in the bulb for the following year.

Flowering Bulbs Recommended planting depth from tip to soil surface (inches) Minimum Spacing (inches) Bloom Time Deer-Resistant
Snowdrops - Galanthus 3-4 3 Early spring X
Windflowers - Anemone 2-3 2-4 Early spring
Crocus 4 4 Early spring X
Scilla 4 4 Early spring X
Tulips- early 6 6 Early spring
Daffodils 6-7 6-8 Spring X
Grape Hyacinth 4 3-4 Spring X
Tulips 5 6-8 Spring
Fritillaria 3 6-8 Spring X
Hyacinth 4 6-8 Spring
Tulips- late 7 6-8 Late spring
Dutch Iris 4 4-5 Late spring X
Allium 1-2 6-8 Late spring/summer X
Giant Allium 2-3 12-18 Late spring/summer X

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