Kelp is one of my favourite seaweeds to harvest, and this past Super Full Moon created some amazingly low tides that were perfect for harvesting!
The coast of British Columbia has some of the greatest diversity of kelps found anywhere in the world. Kelps are part of the Brown family of seaweeds, known as the Phaeophyceae family, which also includes the Wracks which grow in the Upper Zone (we’ll talk about them another time). Brown seaweeds contain many beneficial compounds such as iodine, fucoidan, laminarin, alginates, phlorotannins and carotenoids. The Brown seaweeds have SO many health benefits including cancer fighting, antidiabetic and immuno-modulating properties. They are anti-inflammatory, antiviral and can help protect us from UV damage and heavy metals. They are also a nutrient dense food, high in many vitamins and minerals. They are the highest in Iodine of any of the seaweeds.
Kelp is great for supporting nearly every aspect of our health. Most of the compounds are made bioavailable with hot water, so my favourite way to use kelp is to add it to anything water based that I am making. Broth, soup, rice, lentils etc. By adding kelps to these dishes we infuse them with a wonderful flavour, but also with things like iodine and fucoidan to help support our health.
Kelps are not for everyone. They should be avoided by people with Hyperthyroidism, Grave’s Disease, or Hashimoto's as the high Iodine content can exacerbate these conditions.
I love Kelp. I feel like they have a bit of a mysteriousness about them because of where they grow. We do not get to see them often and it is a special time when we get to walk out and harvest them. Growing season for all seaweeds is from the Winter Solstice to the Summer Solstice. The ideal harvesting window for seaweeds is from the Spring Equinox to the Summer Solstice. After that they begin to focus on reproduction, not growth. So timing is essential!
Kelps grow in the colder, deep waters of the Lower Zone and the Sub-tidal Zone, meaning that they are not always exposed at low tide. To harvest the larger kelps such as Sugar Kelp and Bull Kelp, which only grow in the Sub-tidal Zone, we need the super low tides that occur in the days following a Full Moon, known as Spring Tides. These tides are not named for the season, they are named for the springing action the Moon's gravity has on the Earth. The tides go even lower if it is a Super Full Moon, meaning the Moon is closest to the Earth. Spring Tides can occur in the days following a New Moon as well, but they are not as substantial as the Full Moon Spring Tides. A more difficult time to harvest kelp is during what are called Neap Tides which occur around the Quarter Moons. This is when there is not a lot of difference between high and low tide, so the kelps will not be exposed.
Harvesting kelp requires planning. You need to keep track of your tide charts and the weather. Keeping track of the Moon and its cycle is one of the best ways to know when to harvest. A super low, morning tide on a sunny spring day, as the tide is going out, just after a Full Moon is the perfect time! Knowing good places to harvest is essential as well. Do not harvest near any industry, or where waters are used frequently by recreational boaters. You want a clean beach that is north of any of this sort of activity since any pollutants will be brought south with the current.
You also need to know what you are harvesting! Don’t go out and just start cutting willy-nilly! Here on the West Coast we are fortunate to only have two toxic seaweeds known as Bleachweed (Prionitis sp.) and Acid Kelp (Desmarestia sp.). Even their names make them sound yucky! Get to know these two and then you are good to go! My absolute favourite book for seaweed identification is Pacific Seaweeds by Louis Druehl and Bridgette Clarkston.
To harvest kelp, bring your rubber boots (or go barefoot if it’s warm enough), some scissors and a bucket. DO NOT rip the kelp up! Just cut the top third of the plant and move onto the next. This allows it to continue growing and reproduce. Of course if it is already ripped up by the current then you can take the whole thing. A low tide after a winter storm is a great time to harvest some beach-cast Kelps.
Give it a good rinse in the ocean before putting it in your bucket. Make sure there are no little creatures tagging along. Also WALK LIGHTLY. I cannot emphasize this enough! You are venturing out into a very delicate part of the ecosystem that is not used to the heavy-footed traffic of humans. There are a lot of creatures that make these tidal zones their home, and they would appreciate not being stepped on.
Be prepared to hang your kelp to dry as soon as you get home. Seaweeds are best when fully dried in the sun within 48 hours of harvesting. They can keep for up to 10 years when properly stored out of moisture and light! I like to drape mine over my garden fence, but a suspended rope or clothes line will work as well.
You will also need to know the harvesting laws in your area. Here in British Columbia we can harvest for personal use without a permit as long as we are harvesting 100kg or less. If you are harvesting more than that, or if your harvest is intended for commercial purposes, you require a permit from the BC Government.
Harvesting season is almost up here on the West Coast. We have one more shot to harvest these Sub-tidal beauties in the days following the next New Moon on June 10th. The tides will not be quite as low as they were with the Super Full Moon, but they will be low enough that hopefully some of the Sub-tidal bounty will be accessible.