From our perspective as sweet pea plants (Lathyrus odoratus), our primary purpose is to reproduce, and flowering is how we achieve that. When we are not flowering, it is a sign that our fundamental needs are not being met, causing us stress and forcing us to focus on mere survival rather than procreation. Here are the most common reasons from our point of view.
We are sun-worshippers at heart. Our internal processes are driven by photosynthesis, which requires abundant, direct sunlight. If you have placed us in a spot that is too shady, even for just a part of the day, our energy production plummets. We simply cannot generate enough surplus energy to create the complex structures of flowers. We will put all our effort into stretching our stems towards any available light source (which you call "legginess") in a desperate search for the energy we need to survive. Flowering becomes a luxury we cannot afford.
Our genetics are coded for specific temperature ranges. While we enjoy warmth and sunlight, extreme heat is our enemy. When temperatures consistently soar, especially at night, we become profoundly stressed. Our systems go into a kind of shutdown to conserve water and energy. We interpret intense, sustained heat as the end of our lifecycle, and our programming tells us to stop flowering and start producing seeds to ensure our genetic legacy. If it's too hot, we will abort flower buds and cease producing new ones.
The soil is our kitchen, and we require a balanced diet. A common mistake is providing us with a fertilizer too high in nitrogen. While nitrogen promotes vigorous, green, leafy growth (which is nice for you, but exhausting for us), it does not encourage flowering. We get stuck in a vegetative state, putting all our resources into leaves and stems. What we truly crave for blooming are nutrients like phosphorus and potassium, which directly support the development of strong roots and, crucially, flowers and seeds. An imbalance forces us to grow in a way that is not aligned with our reproductive goals.
Our roots are our connection to the world. They need consistent moisture to transport nutrients and water up to our stems and buds. If the soil is allowed to dry out completely, even just once, it causes a shock to our system. Flower buds are highly sensitive and will be the first thing we sacrifice to conserve water. Conversely, if our roots are sitting in soggy, waterlogged soil, they begin to rot and suffocate. A damaged root system cannot gather any nutrients or water, leading to a weak plant that is struggling to stay alive, let alone flower.
This is the most crucial feedback loop you can engage in with us. From our perspective, a flower that fades and forms a seed pod is a success—our mission is accomplished. Once we have set seed, our hormonal directive is to slow down and direct all remaining energy into maturing that seed. However, if you consistently remove the fading flowers (deadheading) before seed pods can form, you trick our biology. You are essentially telling us, "Your mission is not yet complete; try again." This prompts us to produce wave after wave of new flowers in a continuous attempt to successfully reproduce. Failing to do this signals to us that we can stop trying.
