Allium (Flowering Onion)
Alliums, or Flowering Onions as they are sometimes called, are found in the same family as garlic, shallots, chives, and onions. Many gardeners often wonder if growing Alliums will cause their garden to smell more like a vegetable patch than an outdoor paradise. Fortunately, the scent is only sometimes detected when the leaves or petals are bruised or crushed and is rarely smelt when admiring these fun plants. On the positive side, rodents and deer do not desire to munch any bulb grown in the onion family which means that all of the Allium bulbs are deer resistant!
These plants will add an interesting texture to your garden with their tall stalks topped by spherical blooms. They will also add great texture to dried floral arrangements as the dried flower heads last an extremely long time. Varieties range in height from 12 inches up to 4 feet at times!
Planting Allium in Outdoor Areas
- Alliums are typically planted in fall. Their roots will form in fall and they will bloom in early spring.
- Choose a planting location that has well drained soil, and receives full to at least a half days sun.
- The spacing for Alliums typically ranges between 4” and 8”. The bigger the bulb, the more space they will need. Alliums do not grow with a spreading habit, they look better when planted closer together.
- The planting depth is going to differ depending on the variety you are growing. As a general rule of thumb, flower bulbs should be planted approximately three times their height in depth. For instance, Allium giganteum (Giant Allium) often has a bulb which is 2-3” tall. This bulb should then be planted 6-9” deep into the ground.
- Plant bulbs “pointy end” up.
- Thoroughly soak the area with water once all the bulbs have been planted. Water as needed while the plant is growing and blooming.
- Once the flowers begin to fade cut and dry or use for fresh cut arrangements, allow the foliage to yellow and die back. The leaves will continue to gather sunlight and make food for next year’s blooms.
- Once the foliage has yellowed and dried, the foliage may be removed by gently pulling it out of the soil. If the leaves do not easily pull away from the bulb, they are not ready to be removed. Your Alliums are now dormant and ready to “rest” until next year!
*How do I tell if my soil is Well Drained?
9. To tell whether or not your soil is well drained monitor the planting location after it rains. After several hours of a rain shower, all precipitation should soak into the soil. If this does not happen a different location should be chosen, or your soil should be amended with additional organic material such as peat humus, composted manure or compost from your home compost bin…If you are still unsure of your soil content you can send a soil sample to your states extension office for testing. If you soil is high in clay content, do not add sand to it, it will turn your soil into concrete. If your soil is sandy and the water drains a bit too well, you will want to add peat moss or humus to enrich the soil, and increase its water and nutrient holding capacity, which will therefore provide a happy home for your bulbs.