Winterizing Lily Bulbs
The natural beauty of a blooming lily is a sight to behold during the spring, summer, and fall months. They are some of the most beloved and rewarding flowers to grow in your home garden and are a variety of plant that should be winterized and protected in areas of extreme cold or wet conditions. This is necessary because lilies cannot withstand the effects of freezing temperatures and continually wet soil conditions. Lily bulbs are at risk of damage from extreme cold temperatures and the onset of winter weather (sleet, snow, and soil saturation caused by heavy rains). Do not despair…You can easily winterize your lilies during the cold season so they can remain healthy and grow beautifully the next spring. There are a few simple techniques by which even gardeners brand new to the process of winterizing and storing lily bulbs may enjoy great success. For best success it is recommended to begin the process of winterizing and storing lily bulbs in early fall even as early as September!
If you are noticing that some (or possibly all) your varieties fail to emerge the following Spring, it’s because they probably froze or remained too wet during the winter months rotting the bulb. However, freezing is usually the culprit. Garden soil or landscape soil normally will provide your lily bulbs with natural drainage unless your bulbs are planted in an area that has a lot of clay, or continually remains wet. I know that digging your bulbs can be troublesome, but if you live in areas that remain extremely cold or wet during the Winter and early Spring months (below freezing or saturated wet soil), then you will need to dig them up every Fall before extreme weather occurs and store them for planting the next Spring. Or treat them as annuals and replenish your supply every year.
Since a lily’s root is a rhizome, and bulbous in appearance, the plant is produced from a swollen underground storage organ known as a corm, it is not a true bulb. Instead it is a tight, concentric ring of succulent scales which are attached at their lower end to a basal plate. However, for simplicity reasons, we refer to them as bulbs. The bulb is inserted into the ground to grow, and should you decide to dig up each bulb, marking where you have planted them is important.
Preparing the Lily Bulbs for Storage
To begin, dig up the lily bulbs to be winterized and stored. If there still remains a green stem at this time, leave at least two inches attached to the bulb (read our article). This will provide extra nutrients to the bulb during storage for next year’s growth and bloom. If the stem is brown, then go ahead and remove it. Be especially careful while digging your bulbs, taking care not to damage the bulb and get as many roots as possible. Timing of this procedure is not that critical, as long as the lily bulb has completed its’ blooming cycle, you leave at least two inches of green stem attached to the bulb (the more the better) if any of the stem is remaining, and you start well in advance of frost, frozen soil, snow, or heavy rainfall.
Next, thoroughly yet gently clean off each bulb under a stream of lukewarm running water. Use fingers or a very light, gentle brush to remove debris and clinging dirt from the bulb. Removing all of the visible clinging soil reduces the likelihood of bacterial infections damaging or destroying the bulb during the storage months. It is also a good idea to remove any damaged, old or diseased scales at this time and once dry I recommend dusting with a fungicide.
Prepare a soil mixture in a container or pot that is damp, not wet and will allow good air circulation around the roots and bulbs. Do not use garden soil! The bulbs should then be placed in an upright position within and stored in a cool place. Remember, lily bulbs never really go dormant and it is a good idea to give the roots room to grow without being crowded. It is also a good idea to place your lily bulbs in a plastic bag making sure there are holes punched into it for release of accumulated moisture and air circulation or use a paper bag. I prefer the latter. Peat moss, vermiculite, sand, and sawdust can also be added to the bags as well. The bulbs should then be placed in a dry, cool place making sure they remain damp and do not dry out, where they will be spared from freezing temperatures. Ideal places to do this are a garage, garden shed or inside your house, such as in the basement. Avoid storing them in a refrigerator, as the temperatures may be too cool and for the most part all refrigerators nowadays have too much air circulating to remove moisture which means your lily bulbs could dry out and die.
Storing the Lily Bulbs for Winter
On a small scale, storing your bulbs in bags is best. Paper rather than plastic is recommended for its porous quality that allows moisture to pass through and not build up, which can lead to growth of bacteria, mildew, mold, and eventually rot the bulb. However, plastic can be used if there are enough holes punched in the bag for release of accumulated moisture but I do not advise the use of plastic for storage. Larger amounts of bulbs can be stored in crates, such as plastic bulb crates or wooden apple crates. Good air circulation and drainage is a must if watering during the winter.
The best storage material for lily bulbs is soil-less potting mix with plenty of perilite (for good air circulation) that is light and aerated. Place a modest amount of the soil less potting mix into the bag, and place the lily bulb into the center of the mix then cover the bulb with the soil less mix. Close the top of the bag with a slight openning to allow moisture to escape. Be sure to label the bag to know its contents when replanting in the spring. Storage should be done in a cool but not freezing, dry spot.
The majority of lilies are a pretty tough bunch and able to cope with most of what the winter weather will throw at them. However, they can be prone to rotting off in extreme, cold, and wet conditions, especially the ornamental and orienpet varieties that originate from mountainous regions, but with a little thought – and minimum of intervention overwintering lilies is quite straightforward.
If you are planting lily bulbs into damp conditions or you live in an area prone to heavy rainfall over the winter period, it will be worth trying to improve the drainage of the soil by placing and mixing in plenty of horticultural grit, perilite, bulky organic matter, and even placing some small rocks below the bulb. It may even be worth creating a low mound to plant your bulbs into to help keep them away from a high water table. You can even consider protecting the area around the bulb from heavy rainfall by covering them with a large cloche or a makeshift plastic tent, a thick layer of good autumn mulch such as straw, grass clippings is also a good idea.
Lily bulbs never really go dormant, and do best when out of the ground for as short a time as possible. If you have the space, I would recommend potting the bulbs right away. I also recommend storing the potted bulbs in an unheated garage or cool basement until spring, then gently pull the roots apart and plant again.
If you can’t pot them up right away or do not have the space, I recommend getting some soil less potting mix, dampen it so it is moist to the touch, dust the bulbs with a powdered fungicide, then store the bulbs in the soil less potting mix in an open container (which you will need to mist periodically to keep it just on the moist side) such as a small bucket. You can cram them in, bulb to bulb, you’re just trying to keep the root system fresh and growing. Store in the basement or garage until you can plant in the spring.