“Spring has returned. The Earth is like a child who knows poems by heart.” —Rilke
On this, the vernal equinox, we think flowers and adorable baby animals hopping and bumbling about, but one of the poems our planet knows by heart has to do with some much, much smaller things. These aquatic unsung heroes of spring are so vital to life as we know it that they deserve a place next to dyed eggs in Easter baskets around the world as icons of spring. They’re responsible for producing fifty percent of the oxygen in our atmosphere. They’re the foundation of the largest food chain on Earth and a superfood. They’re called phytoplankton, and they’re really making a splash in culinary circles.
The path this fascinating flora took to your dinner plate wends back untold eons. Phytoplankton, from the Greek for “wandering plant”, is sometimes referred to microalgae, but that doesn’t tell the whole story. Until the nineteen-seventies, in fact, no one knew the whole story. Advancements in microscopy made it possible to see cyanobacteria, which are so small we couldn’t catch them in any sort of net. These cyanobacteria are some of the oldest and most primitive life forms on Earth and are thought to be the first to ever utilize the photosynthetic organelles known as chloroplasts. In short, cyanobacteria were photosynthesizing long before plants came on the scene.
Apart from bacteria, phytoplankton is made up of single-celled plants (i.e., microalgae) that are broken down into two main classes: dinoflagellates, which have whip-like tails for locomotive purposes, and diatoms, which rely on ocean currents to get around. Both have shells, but the shells of diatoms are more rigid, which is why diatomaceous earth is so useful. In spite of their differences, all of the things that make up phytoplankton have a lot in common. For example, they all require a good mix of minerals to be present in the water around them. Minerals like nitrates, phosphates, silicates, sulfur, and calcium are transformed from their raw states into proteins, fats, and carbohydrates. This ability to create the building blocks of life from inert pieces of their environment is what makes phytoplankton the foundation of nearly every single oceanic food web. Some phytoplanktons are capable of fixing nitrogen and can live even where nitrates are low. Other factors that inhibit growth include iron availability, water salinity, temperature, wind, and predation. When conditions are right, though, populations can boom.
Explosive growth in a phytoplankton population is called a bloom. Blooms can be beautiful, creating vast green spirals on the ocean that span hundreds of square miles and can be seen from space with the naked eye. They can last for weeks in spite of the only few-day-long lifespan of your average phytoplankton. Like many of the nature’s most beautiful creations, blooms can also be deadly. In these cases, biotoxins released by phytoplankton create what are known as “red tides” (or, less dramatically, harmful algal blooms). Even after a particularly large and seemingly benign bloom, dead phytoplankton sink to the ocean floor, where the bacteria that feast on them deplete oxygen levels in the water, suffocating all other aquatic life and creating dead zones in lakes and oceans alike.
One of the largest blooms the world over happens when winter’s grip on the northern hemisphere loosens. This phenomenon, called the “Spring Bloom”, occurs in North Atlantic, sub-polar, and coastal waters. As with much of Earth’s poetry, the classic theme of creation from destruction, life from death, is played out here on a grand scale. The waters of winter, made turbulent by dropping temperatures on the surface, disrupt the calm layers present the rest of the year. This disruption of what’s known as the stratified water column churns the sea, bringing nutrients up from the deep while pulling phytoplankton down into the depths from the surface. After losing billions upon billions of their compatriots to this cycle, the phytoplankton remaining in the euphotic zone (the area close to the surface ideal for phytoplanktonic growth) are surrounded by the recently dredged up nutrients. Increased spring sunlight and warming temperatures restore the stratification of the water column, creating optimal growth conditions. From winter’s clutches, the Spring Bloom bursts into rich and verdant life.
During these blooms, animals from the tiniest zooplankton to the largest whales feast, and it’s no wonder. Phytoplankton are loaded with amino acids, essential fatty acids, vitamins, antioxidants, and major and trace minerals. Very few foods out there have this kind of combination of the raw materials required for cell growth and repair, which is why we land lovers champion this superfood today.
Rather than relying on natural blooms, phytoplankton is now often farmed. Whether in controlled natural environs or highly controlled artificial ones, aquaculture allows us to create a fresh, pure, and dependable source. The idea isn’t a new one. In fact, during the German blockades of WWII, the UK was toying with the idea of feeding its population with farmed phytoplankton from its many fertile lochs. While eating pure phytoplankton might sound more like something from a dystopian novel than a culinary treat, sparing use enhances dishes with the flavor of the ocean, adding a nutritionally rich depth of taste seldom found with other ingredients. After it’s harvested, phytoplankton is freeze-dried for maximum freshness, so when it does find its way to your plate, you aren’t missing out on the incredible health benefits.
Here at Beaujolais, you’ll find phytoplankton sprinkled atop scallops, mixed into sauces covering clams, and anywhere else that might delight Chef Gilbert at the time. Ask your server about which dishes currently feature this delicious addition, and dive into one of the truest rites of spring.