Here at Cantosa Farm, we think plants and seeds are amazing. We decided to produce a seed germination time lapse video. We set up a time-lapse camera in our greenhouse to see what happens in the first few days of germination. When we cut the night time out of our first video we discovered that a lot goes on at night so we decided to redo our video with a light during the night hours. The video was shot over a 72 hour period in late February 2018. It follows the seedling in the middle of the picture but also reveals what happens to the leaves in the surrounding seedlings during the day/night sequence. We think it is pretty fascinating!
Seed Germination Time Lapse Video
We hope you enjoyed watching our seed germination time lapse video as much as we enjoyed making it.
In this post, we will explore the science behind germination of seeds. I have tried to make it as reader-friendly as possible with a minimal amount of scientific terms. This is a general guide based on scientific research.
What is germination?
Germination is the growth of a plant from an embryo inside a seed, of which, is the result of pollination via insect or wind between two plants of the same kind.
What are the requirements for successful germination?
Successful germination conditions closely mimic the ecological conditions of the plant’s natural habitat and therefore will depend on several factors being present at a particular time: the correct range of temperature, water, oxygen and either the presence or absence of light (depending on which is favourable for the specific variety). If any of these conditions are not met, the seed may enter a period of dormancy until the conditions are better or deteriorate through decomposition.
Some call it ‘the elixir of life’. Around 75% of Earth’s surface is water and it is important to every living thing: humans, animals and plants.
Seeds require water for germination as they are often very dry. They can take up water many times relative to their dry weight in order to resume growth by producing more cells. The process of uptake of water is called ‘imbibition’ and leads to the swelling and breaking of the seed coat.
Most seeds contain a small store of energy in the form of starch, protein or oil. When the seed imbibes water, enzymes are activated which break down the stored food resources to useful chemicals (energy). The seed will use this energy to send down a root and send up the first leaves which will produce chlorophyll through the process of photosynthesis. This is converting energy from the sun to useful energy for the plant. At this point the food source from the seed would have depleted.
Seeds and plants require oxygen in order to convert food to energy for cellular processes, nucleic acids and carbohydrates. It also helps with the elimination of toxic wastes. Oxygen from the atmosphere is also contained within pockets of the soil. This is why it is important not to waterlog plants and seedlings because it will remove oxygen from the soil. Interestingly, the symptoms of an overwatered plant can be the same as an underwatered plant.
Seeds have a temperature range within which a seed will germinate. Again, this will need to be close to the natural habitat of the seed. i.e. warmer for tropical countries etc. Seeds will not germinate outside of this range and may enter a dormancy until the preferred temperature range is consistent.
However, some seeds require a period of cold temperature in order to germinate. This would mimic a natural period of winter. The seed will know that it needs to enter and pass winter in order to survive. This can be overridden by a process of cold stratification. This is where seeds are placed in a fridge or freezer for a set amount of time before sowing.
Light or Darkness for Germination
Some seeds need to be placed on top of the soil because they will only germinate with the presence of light rather than being underground. One example where this is useful are forests which will have dormant seeds on the ground. The seed will wait for a tree from the canopy to fall in order to sprout. This action ensures that it will have the best chance for continuous sunlight in order to produce chlorophyll and therefore sustain life.
We hope you enjoyed watching our seed germination time lapse video made here at the farm!