Why grow lilies in pots when they are so easy to grow in the ground? For those of us who desire to grow less than hardy varieties, container growing may be the only solution as less hardy varieties will not survive a winter in the ground. Short-stemmed or dwarf lilies are an excellent choice for container gardening and help to beautify your surroundings and landscape.
There are also many gardeners who prefer pot culture as they find them more convenient to care for. What ever your reason may be, here you will find the information you need to grow them successfully.
When we were open to the public visiting the lily gardens, we grew and sold thousands of potted lilies for people to take home over a number of years. We were proud to grow the healthiest potted lilies you would find anywhere, grown in the great outdoors under natural conditions and during the same typical growing season as our lilies in the ground. We started potting lilies in late March and continued to the first week of May. The information that follows is the exact procedure used during our years in the greenhouse & nursery business as well as when we decided to specialize in lilies. Of course, the methods were fine-tuned over the years.
After potting, they are watered until it is coming out the drainage holes of the pot, then slow release fertilizer is added on top the soil. Trays are moved to the unheated shop where they sit for a minimum of 2 weeks to root - keeping them on the cold side encourages them to develop healthy, extensive root systems before they send out shoots, just as they do in the ground. They are not watered at all during this period, and they don't require it because they are kept cool, in the dark and don't dry out. By this time most of them are just beginning to poke through the soil, and it's time to move them outdoors into some sunshine. Out they go, often going through a frost or two before really starting to grow in May. Once sprouted, we only protect them from freezing if temperatures threaten to go below -5 celcius.
Knowing when to water the lilies takes experience and attention to detail at this stage - typically they are watered only when the soil is visibly dry, about every 3 days from May to the end of June. Windy days can mean watering every day, or rain can mean no watering for days on end! Dwarf varieties are ready to bloom by the middle or end of June, the rest are approaching 3 feet in height and watering is now needed on a daily basis, depending on the winds and temperatures.
After flowering, the inflorescence is cut off so the plant spends its energy building a bigger bulb rather then producing seed. We let up on the watering, gradually letting them dry out now until we discontinue watering at the end of August so the stems can mature and dry off. Any bulbs I wish to keep over winter remain in the pots, which go back into the unheated shop with a couple mothballs in the pot to keep the mice away. Of course, the dead stems are pulled off before placing them in storage. Sound simple doesn't it? It really is, and I encourage you to try it yourself especially if you want to grow those fragrant, less than hardy beauties year after year!
Things to consider before planting:
- Length of time they will remain in pots
- Stem height at maturity
- Container size and suitability
- Your available time to care for them
- Number of bulbs to plant per pot
Large pots, the bigger the better is my motto! The larger the soil volume in the pot, the less chance there is of baking or freezing the bulbs within. This is especially important if the pots are black or dark colored, and they sit in full sun all day.
Orientals, orienpets, trumpets and asiatics that grow taller than 24 inches require a sturdy pot that will not tip over easily as the stems grow to mature height and become top-heavy with flowers. Typically, we put one oriental or orienpet bulb per one gallon nursery pot. The size of one gallon is misleading when it comes to nursery pots because at first glance it is easy to see that it would really only hold about a half gallon - don't ask me why the nursery trade sizes or labels things this way! The actual dimensions of the pot are what counts in the end, and the one gallon pot is usually 6 inches in diameter and 8 to 10 inches in depth. When planting 3 bulbs to one pot, we prefer to plant in a container with an 8 to 12 inch diameter, with at least the same depth as the one gallon pot. You may wish to place rocks at the bottom of the pot prior to adding soil or bulbs, in order to add weight so it won't tip easily in wind. MAKE SURE there are drainage holes at the bottom of the pot no matter what size, color or shape it is - drainage is the most important element with lilies! Don't settle for a layer of rock or gravel as drainage without holes, use pots with holes! Many a gardener has told me about how they thought they'd spend less time watering by using pots without drainage holes, or how they didn't like the water running out the bottom onto their deck, so they blocked the holes - only to find the plants rotting away a week or so after some steady rain filled the pots and they didn't notice until it was too late. This is more apt to happen with planters full of annuals since you can't see the soil surface once they fill out, but the same can happen with lilies. All the water may be sitting at the bottom 3 inches of the pot (exactly where the roots and bulb are) and you won't know it because you can't see it.
Another key consideration when choosing pots is the depth, all lily bulbs need at least 4 inches of soil over top the bulb to grow well and an inch of soil at the bottom. Add an inch to the top for watering purposes and that means you should not plant in anything shallower than 6 inches. Be aware that the smallest bulbs need these minimums, bigger bulbs need more soil over the top, closer to 6 inches if the stems are to remain sturdy at maturity.
Soil and Potting Mixes
Lilies LOVE sandy soil, no question about it and my observations and experiments with different mixes over the years proves it. In every case, when sand dominates the potting mix, bulbs develop very healthy, thick roots in abundance. Bulbs increase in size quite dramatically in sand, in contrast to using a basic potting mix without sand. Basic potting mixes tend to encourage bulb and root rot because of the high peat content, and I also notice the bulbs seem to decrease in size rather than increase - especially when overwatered. Because sand makes up the majority of the mix and holds no nutrients, fertilizing becomes more important.
Recommended potting mix for lilies:
2 parts sand
1 part loam
1 part peat
The best investment you can make in ANY of your plants is in the fertilizer. The rewards of regular feeding are well worth the effort, resulting in healthier plants, bigger flowers in bigger quantity and the ability to resist pests and disease with ease. Fertilizer is especially important in the early growth stages. Compare it to building a house - you want a sturdy foundation (your plants need sturdy root systems) and you know the strongest wall is useless if the foundation can't handle it! The first decision comes in choosing the type of fertilizer that suits you best. I prefer to use slow release pellets because it saves me time and I don't have to remember when I last fertilized. It is applied once at the beginning of the season and that's it. You might prefer to mix water soluble types and water with them weekly, or perhaps you are big on organic types such as fish fertilizer. Another worthy tip is to only use fertilizers mixed with water on pots that are already moist, never apply fertilizer to a dried out pot because it will surely result in leaf burn. Whatever you may prefer, just be sure to establish a routine and use it - you won't regret it! Regrets only happen when you disregard the mixing instructions, so please read them and follow them to the letter because twice the fertilizer doesn't mean twice the bloom - it usually means damage to the plant.
For bigger blooms and bulbs the next year, be sure to apply tomato fertilizer at least once immediatly after blooming is finished, twice would be better yet. In this case, I would suggest using a water soluble tomato fertilizer mixed at full strength according to the package directions, any vegetable fertilizer will do the trick.
What To Do After Planting
Ideally, you want to keep your potted bulbs quite cool for a couple weeks while they root. A temperature of +5 Celcius is perfect. After they poke through the soil, you still want to keep them as cool as possible, but this time in light. Keeping them cool rather than warm will ensure, strong, sturdy stalks instead of weak stems. I encourage you to place your potted lilies outdoors after potting and leave them there day and night - no need to cover or move them inside unless temperatures go below -5 Celcius. The bulb inside the pot is insulated by the soil, and if the lily sprouts in cool temperatures it can handle a few degrees of frost after sprouting without any damage. Keep them cool in natural conditions from the start!
The biggest danger to potted lilies is overwatering, I just can't stress it enough. Lilies love plentiful moisture, but only when good drainage is also present. Waterlogged bulbs will rot quickly and easily, usually you won't even know this is occurring until you unpot the bulb or it starts to look sickly for no apparent reason. Water when planted, then not again until dry after poking through the soil. From that point on, water only when dry.
How Long To Bloom?
Depending on the variety grown, 2-3 months from potting results in flowers. Weather makes it difficult to predict exactly when they will bloom when grown outdoors. Orientals take 2-4 weeks longer, as will most orienpets and trumpets. That's why we start potting these varieties in March, with asiatics and LA's to follow in late April.
After Blooming Care
Cut flower tops off to promote bulb growth, but be sure to cut no more than one-third of the stem total. Lilies gather their energy through photosynthesis, this makes it important to leave them with as much foliage as possible so they can grow and flower admirably the following year. Continue to water the pots when dry until late August then reduce watering so the stems can yellow and wither away. Yes, they will look unsightly for a time, but wait until they are quite yellow and brown before cutting the stem off at soil level. Pots can then be stored as is, without watering, in a cool spot for winter or unpotted and bulbs placed in peat or sawdust shavings in a cool place such as a cold pit or refrigerator, ready for potting the next spring.
A Note Of Caution: Quite frequently I am asked if the bulbs can remain in the pot and left outdoors for winter, and my response is always a resounding NO - not in my climate anyway. In a typical winter if a pot was left above ground, regardless of how big it was the bulbs inside would be mush by spring time. It doesn't matter if they are zone 1 or zone 3 rated, they will be mush if left above ground. You could however, dig a hole anywhere in the ground and put the pot and all in that hole, push dirt level with it and it would be just fine the following spring with nothing more to do than pull it up, clean the outside and start caring for it just as you did the previous year.
In spring 2013 a friend was quite happy to prove me wrong. She had asked the previous fall if she could leave some in pots and I told her no. Apparently she did anyway and in May she could see sprouts coming! She let me know and I was shocked, truly. The following week I was working in the gardens here and happened to walk out behind the shop. Imagine my surprise to see crates of lilies (and not asiatics, but non-hardy Star Gazers of all things!) on the ground with sprouts nearly 6 inches tall happily growing! Behind the shop is where crated lilies grown and cut for weddings each year reside, and the previous fall it had snowed before I had a chance to clean up and trash what was left, which was nothing but bulbs in the soil as the stems were cut off. I was totally baffled by this until my husband pointed out that they were under 6 feet of snow back there - no way they would have survived otherwise! This would also be the reason why my friend's bulbs survived in their potted homes since we had an abundance of snow in the area the winter of 2012-2013.