Planting them in the garden is best done in a warm, sunny location with adequate, moist soil that is well-drained. This mimics weather conditions in order to encourage the plant to produce a thicker stem and better withstand this kind of environment.Ĭosmos seedlings are sensitive to temperatures below 57.2 Fahrenheit (14☌) and can be damaged by frost for prolonged periods of time. The second approach is to utilize a fan and blow a gentle breeze toward them. The first method is to brush your hand against the leggy cosmos seedlings once or twice a day, which provides the plant with some resistance. So what can we do to force these leggy seedlings to grow stronger and sturdier? There are two ways: So we’ve established that l eggy cosmos seedlings are not sturdy enough to withstand things like natural weather such as strong winds and rain. This is absolutely fine, I just continue to increase the height of the heat lamp whilst making sure that the source is still 2.5 inches above. You may find that you will need to continually increase the height of your artificial light as the cosmos seedlings grow taller. Remember if you have opted for artificial light, it is important that your light is close enough to the seedlings so they can soak up as much of it as possible for photosynthesis. If you are concerned about not being able to provide them with enough natural light, you can supplement them with artificial fluorescent bulbs placed within 2.5 inches of your seedlings. Without adequate sunlight, you will put your seedlings under unnecessary stress, which will, in turn, cause them to become leggy or worse, wilt and die. I hope this answers your question and that your seedlings bounce back soon.So the absolute number one focus needs to be that you are ensuring that your seedlings are getting enough light. However, it would still be worth checking these other potential causes to make sure everything else is on point.

I believe your issue stems from your original grow light which, in my opinion, was underpowered. Other reasons for leggy seedlings include temperatures that are above the desired range, overcrowded seedlings, or, in rare cases, lack of nutrients in the medium. Only try this method if the seedings have produced their first set of ' true leaves' (the ones that look like cannabis leaves). If the lighting is adequate, the seedlings will continue to develop in a more compact manner. Once the lighting issue is corrected it is possible to carefully, and I mean carefully, transplant the seedlings into a deeper container so you can bury the majority of the leggy stem and allow the top portion of the seedling at the base of the soil. Other Potential Causes for Leggy Seedlings Ideally, cannabis seedlings would receive 20-40 watts per square foot of space. These systems will have the wattage and spectrum needed to beef up your seedlings and to grow cannabis full-term. However, if you plan on continuing the hobby of indoor cannabis cultivation you may want to invest into a flourescent or LED light system designed specifically for plant growth. Hopefully, the change you made can save your seedlings.

That being said, four lights will be better than one and your new system should outperform your old grow light. Unfortunately, the grow lights you are describing (that screw into a regular base socket) are not typically powerful enough for growing cannabis. When germinating, the cannabis seedlings do not need light but after sprouting they need adequate light to grow properly. From your description I would guess you did not have adequate lighting for your little ones when they sprouted.

Fixing leggy seedlings