Lilies do not flower if the bulbs are too small or not yet mature, over crowded, planted too shallow or if they are located in too much shade. Some lilies do not flower if the Winter temperature is too mild as they require a period of cold weather to bloom.
Lilies require lots of sun, good consistent soil moisture and not too much fertilizer to flower properly.
Keep reading for an explanation for why your lilies are not flowering and for all the best practices to ensure your lilies flower well the following year…
1. Size and Quality of Bulbs Can Affect Lily Flowering
If your lilies are not flowering a year or so after planting then this may be because of the size and maturity of the bulb.
It takes a lot of energy for a bulb to flower and small bulbs often do not have the energy and resources required for the lily to grow and display flowers in the first year.
Instead they redirect their energy from displaying flowers, to growing and establishing in the new soil conditions. As the bulb grows and matures it is more likely to flower the following year.
Larger, more mature bulbs have a far better prospect of producing a lilies with flowers as they have greater energy stored for the plant to flower in Spring.
When choosing bulbs for lilies or any flowering plants in garden centers, it is important to be discerning about the selection of your bulbs ensuring that you buy the biggest healthiest looking bulbs possible to ensure healthy lilies and good display of flowers after planting.
2. Over Crowded Bulbs Causes Fewer Flowers
A common reason for lilies not flowering is that the bulbs are planted too close together.
If the bulbs are overcrowded then they are competing with each other for space, nutrients and moisture and sunlight when the green leaves emerge in Spring.
The solution to this is to dig up the bulbs and plant them a more appropriate distance so that each lily has access to all the resources required for flowering.
To ensure the best prospect of a flowering lily plant each bulb at least 8 inches apart. This ensures the lilies are close enough for a good display of flowers and have enough space to thrive.
If you lilies are not flowering and you know they are spaced too close together, dig them up (preferably in the Fall) and space them appropriately so they have enough time to adjust to their surroundings before growing and flowering in the Spring.
3. Shallow Planting of Lily Bulbs Reduces Flowering
The depth at which your lily bulbs are planted can affect flowering. Bulbs that are planted too shallow can suffer from frost damage (which prevent lilies from flowering) whereas bulbs planted too deep can either flower later or not flower at all.
The best practice for planting lily bulbs is to plant the bulbs to a depth of 4 times the diameter of each bulb. This provides protection in Winter and allows the bulb to grow strong and healthy in the Spring.
4. Lilies Prefer Full Sun for Blooms
For most lily varieties around 6 or more hours of sun per day is preferred for displaying flowers.
With a good 6 hours of sun the lily has the energy it requires for flowering whereas lilies planted in partial shade or full shade often grow but do not flower.
If your lily is in a shaded area of your garden consider cutting back any overhanging tree limbs or foliage surrounding your lilies to allow for more light.
If it is not possible to create more light by cutting back other plants and trees then the best option is to wait until Fall when the lilies foliage has died back and dig up the bulbs to relocate then in a sunnier part of the garden.
Do not try to transplant the lilies in the Spring or Summer whilst growing as this causes transplant shock.
In a sunnier location your lilies have more energy which should result in a good display of flowers.
Do consider that in full sun there is a greater risk of drought so it is a good idea to mulch the ground around the lilies with compost to help conserve water.
5. Lilies Require a Cold Winter to Display Flowers
Once of the most common species of lily is the Asiatic lily which actually require a cold period in the Winter to flower in the Spring (a process known as vernalization)
This is because the bulb has adapted to a seasonal cycle of temperature change so the bulb knows when to initiate growth and produce flowers at the correct time in the Spring.
Asiatic lilies are adapted to the temperature pattern of temperate climates so If you are growing Asiatic lilies in a warm climate rather then a temperate climate then the Winter may not be cold enough to go through the vernalization process and the plant may not grow well and not flower.
There is not much you can do (if you live in a hot climate) to promote flowers from Asiatic lily bulbs if the Winter is mild rather then cold, so it is best to select the apprioate lily species that suits your climate.
If you live in a hot climate then the Easter lilies species is a more reliable lily for flowering as it does not require the process of vernalization.
6. Too Much Nitrogen Causes Foliage with Fewer Flowers
Lilies tend to grow best in rich soil with lots of nutrients and often do not require added fertilizer to flower.
Too much fertilizer (especially if high in Nitrogen) can often promote lots of green foliage but with few flowers particularly if it is applied before flowering in the early Spring.
Once you have applied fertilizer to a developing lily there is not much you can do to promote flowering, apart from scale back the use of any fertilizer and wait for the following year.
For lilies that are in poor soil or perhaps in potting soil where they may have exhausted the nutrients a fertilizer applied after flowering can be useful.
After flowering the green foliage of the lily is storing nutrients and gathering energy from the sun to store in the bulb for next years flowers so a well balanced all purpose 10:10:10 NPK is suitable or perhaps a tomato feed which is high in potassium which can support blooms and root development.
7. Removing Leaves From Lilies Too Early Reduces Next Years Flowers
In neat and tidy formal gardens some gardeners may cut away the foliage of the lily after its flowered rather then wait for the leaves to turn yellow and brown in the Fall.
However if you cut away the leaves of lilies after flowering then they cannot store energy in the bulb for the following Spring so they may not display flowers.
The leaves of the lily are still living after flowering and use the rest of the Summer and Fall to draw up nutrients and attain energy from the sun which is used for the following years growth and display of flowers.
It is best practice to wait until the leaves have turned yellow or brown at the end of Fall before cutting away the foliage to promote the lilies flowering.
8. Drought Can Affect Lilies Blooming
Lilies require a moisture balance where the soil is consistently moist but not damp or boggy.
If the soil is slow draining (because of clay soil or boggy areas) then this can cause the bulbs of your lilies to rot in the ground especially over Winter.
However if the soil is too dry and then the bulbs do not have the moisture required to grow and flower properly.
Soil can be too dry for lilies because:
- Of sandy well draining soil that drains very quickly and does not hold any moisture.
- Too much sun directly on the soil dries the soil out.
- Tree roots are competing with the bulbs for moisture.
To achieve the optimal balance of moisture for successfully flowering lilies you should plant them in soil that has been amended with compost or leaf mould.
Compost and leaf mould have the capacity to hold moisture but still have a porous structure that allows excess water to drain away from the bulbs so they are not sat in saturated ground which are the ideal growing conditions for lilies.
A compost mulch applied in the Spring around the lilies can help to retain moisture and continue to improve the soils nutrient profile and structure so that the lilies do not suffer from drought.
Give the soil a good soak if there has been a lack of rainfall and check the soil to a fingers depth to see if you can detect moisture. If the soil is starting to dry then water the ground but if its still moist and the mulch is conserving moisture effectively then you do not have to do extra watering.
With good consistent soil moisture (yet well draining soil to avoid the lilies bulbs rotting) the lilies should flower well the following year.
- The reason for lilies not blooming is often because the bulbs are too small, overcrowded or planted to shallow. Not enough sunlight, drought, too much fertilizer and mild Winter temperatures can also prevent flowering.
- Cutting away the leaves after flowering can prevent lilies from flowering the following year. The foliage should be in a sunny location to help store energy in the bulb for the following years flowering.
- Plant lilies in full sun, with good compost (to help to avoid drought) and space the bulbs appropriately. Asiatic lilies prefer a cold Winter to flower whereas Easter lilies are better for growing and flowering in climates with mild Winter temperatures.
- Lilies do not necessarily flower in the first year particularly if the bulbs are not mature or suffer transplant shock and often flower better the following year.