The reason for spider plant foliage not growing is usually because the temperature is too high or too low, the spider plant is too shaded, a lack of nutrients in the soil or due to Winter dormancy when growth slows significantly.
Spider plants do not produce their plantlets (also known as spiderettes or babies) due to too much fertilizer which promotes foliage growth at the expense of the flowers and because they require a period of 12 hours of uninterrupted darkness at night for three consecutive weeks.
Keep reading for why your mature spider plant (Chlorophytum comosum) is not growing and why your spider plant is not producing plantlets or babies for propagation…
Why is My Spider Plant Not Growing?
Spider plants typically grow more in the Spring and Summer and the growth can slow considerably during a Winter in response to changes in temperature and light.
Here I have listed the reasons for for a mature spider plant to stop growing in the order of most common causes:
Temperature
The most common reason for spider plants not growing is because the temperature is too low or too high.
The optimal temperature for Spider plants to grow is between 65°F (18°C) 75°F (23°C) during the day and around 55°F (12°C) at night.
If temperatures are significantly warmer or cooler then this range then your spider plant may stop growing.
(Frost damage can cause spider plant leaves to turn black, read my article for more information).
Spider plants are adaptable and can live in a range of conditions but to ensure good growth try to keep the temperature between 65°F (18°C) 75°F (23°C).
If the temperature is significantly colder then 55°F (12°C) for a long time or exceeds 80°F (27°C) then the spider plants leaves show stress by stopping growing, turning brown and can die back.
A spider plant usually recovers well once it is in its preferred temperature range.
(If you think your spider plant is dying read my article how to revive a dying spider plant).
Low Levels of Light
Spider plants grow best in bright, indirect light. Whilst they can tolerate shade, a lower intensity of light or less hours of sunlight can slow the growth or your spider plant so it appears to be not growing.
This is why in Winter your spider plant often stops growing in reaction to less light.
If the spider plant is in consistent heavy shade then its does not grow at the same rate and the leaves can turn pale, limp and the variegated varieties can lose their colors and turn completely green.
Spider plants can adapt to lower levels of light but to really promote growth then you should locate the plant in a brighter area.
I must emphasize it is important not to place spider plants in direct sun, particularly after been heavy shade as this turns the leaves of the spider plant brown due to sun burn and drought stress.
With bright, indirect light your spider plant should start growing again.
Lack of Water During the Active Growing Season
Spider plants can grow all year in our homes as indoors tends to provide the right sort of stable conditions for growing but they grow most notably in the Spring and Summer.
If they suffer drought stress during active growth then the spider plant can stop growing.
Drought stress can occur because of:
- Not watering often enough.
- Watering too lightly.
- Low humidity.
Spider plants are tropical and prefer higher levels of humidity then is typical for indoor environments.
Spray the spider plants leaves with water at least once per week and perhaps more during Summer or in dryer areas to create a humid-micro climate that recreates the conditions of its tropical habitat.
For spider plants to grow during Spring and Summer the soil should be watered with a generous soak to ensure that it is evenly moist all the way to the roots, but the top inch of the soil should dry out between bouts of watering.
When the top inch of the soil feel dry this indicates the perfect time for watering to achieve the optimal balance of moisture so that the spider plant has enough water for active growth yet not too much that it would cause root rot.
(To learn all the best practices for watering spider plants so they grow to their best read my article, must know tips for watering spider plants).
Lack of Fertilizer
Spider plants can stop growing due to a lack of nutrients. If the spider plant has been in the same pot for years then the roots can exhaust the soil of nutrients which can slow down growth of your spider plants in the Spring and Summer months.
Spider plants grow to their best with regular feeding during active growth.
However fertilizing too frequently or too high concentration of fertilizer can also cause the spider plants leaf tips to turn brown as a sign of stress.
So it is best practice to use a half strength liquid house plant fertilizer once per month from Spring until mid Summer so that the spider plant has all the nutrients it requires to growth healthy.
Spider Plant Babies Not Growing for Propagation
If your spider plant is not producing spider babies, this is because the plant has not matured, the pot is too large which redirects energy to growing roots rather then producing babies or because spider plants are short day plants that require darkness to form flowers from which the babies develop.
Applying too much fertilizer can also promotes foliage growth at the the expense of flowers and therefore the spiderrettes.
Spider plant babies form after the spider plant has produced its small white flowers which can be very subtle.
However the spider plant is a short day plant that only flowers if it has at least 12 hours of uninterrupted darkness every night for about three weeks.
This period of darkness indicates to the spider plant that this is the time to produce flowers in its native environment.
To replicate this in your home ensure that the spider plant is in a dark room for at least 12 hours an evening.
If the darkness is interrupted by turning on a light in the middle of the night then this can prevent flowering and the developments of plantlets.
If necessary use a light excluding cloth over your spider plant for at least 12 hours a night.
Larger Pots Prevent Spider Plants Developing Babies
Spider plants tend to flower more frequently (and therefore produce plantlets) if the are relatively root bound in their pots.
By constricting the roots in a pot this can put spider plants in a state of stress which promotes reproduction in the form of developing plantlets as the spider plant is trying ensure its survival in less favorable conditions.
If the spider plant is in a larger pot its tends to redirects its energy into growing the root systems and not the foliage or plantlets.
If the plant is in a large pot with lots of compost then there is less urgency for reproduction which is why the plant is not flowering or producing plantlets.
Larger pots also dry out at a slower rate which can increase the risk of root rot.
Plant spider plants in pots or containers that is slightly larger then their root ball to promote the development of flowers and plantlets.
Key Takeaways:
- If your spider plant is not growing this is often because it is in too much shade, the roots have exhausted the soil of nutrients, drought stress due to under watering or the spider plant has stopped growing during its Winter dormancy.
- Spider plants do not produce plantlets or babies if they are not in at least 12 hours of darkness every night for three weeks as they are short day plants. Fertilizing spider plants too often causes them to not produce flowers or babies for propagation.
- The optimal temperature for spider plants to grow is between 65°F (18°C) 75°F (23°C) during the day and around 55°F (12°C) at night.
- Spider plants grow more in pots that are just slightly larger then the size of the root ball.