Another name for Wasabi is Japanese horseradish, Wasabi is actually the source of the hot, pungent seasoning popularly served with sushi, and it is also used to season nuts and other savory snacks. Wasabi has strong taste and the heat are well-loved by most people who like spicy flavors.
Wasabi plants actually prefers complete shade, which makes it ideal for gardens that don’t get a lot of sun. However Wasabi is a finicky plant, and most serious growers more often turn to greenhouse culture to grow the plant. The Wasabi plants are usually planted from potted nursery starts in the early spring. The rhizomatous stalk will not be ready for harvest until the following year.
Furthermore, the entire wasabi plant is edible. The thick stalk of the mature wasabi plant is what is ground up for making wasabi sauce or paste. The wasabi plant stems and the leaves are also edible and can be used in soups, salads, smoothies, or stir-fry dishes. The wasabi plant stems can be chopped up like chives or celery to mix in with tuna or egg salad or to garnish potatoes. Below is the basic information about wasabi plant;
The botanical name: The botanical name is Wasabia japonica
The common name: The common names are Wasabi, Japanese horseradish.
The plant type: Wasabi is a perennial vegetable.
The mature size: The mature size is about twenty-four inches tall.
The sun exposure: The plant prefers full shade.
The soil type: The plant does well in moist, rich, well-drained soil.
The soil pH: 6.0–7.0 (slightly acidic to neutral)
Plant hardiness zones: USDA hardiness zones eight through ten.
The native areas: Wasabi is native to Japan
How to Grow Wasabi Plants
Actually growing wasabi plants is a little bit difficult because their growing needs are so specific. The Wasabi plants require shady conditions, uniformly moist but not wet soil, and the temperatures that are between forty-five and seventy-five degrees Fahrenheit without a lot of temperature swings. If you actually have such conditions in your garden, you can plant the wasabi in the spring, preferably from a well-advanced potted nursery starts at least one foot tall. If conditions are less than ideal, wasabi plant can be grown in containers, which can be easily moved around to keep the plant in perfect conditions.
If you are planting in the garden, make sure you choose a shady location with a well-drained, slightly acidic to neutral soil. If your soil pH is outside this range make sure you check it frequently and then add the necessary amendments to adjust the pH level.
Wasabi Plant Care
Light requirement: Wasabi plants do not do well in direct sunlight, you need to make sure the plants are shaded. You can easily create a shade barrier with fabric or a folding screen. The container Wasabi plants can be moved around to keep them in the shade.
Soil requirement: The wasabi plants in the garden actually require a rich consistently moist soil with a slightly acidic to neutral pH. If you are growing the Wasabi plants in containers, you can use a 1 or 2-gallon pot with a ten inch planting depth. Just mix up some rich soil with compost that is slightly heavier than potting mix medium, so it will hold moisture. Plant your nursery starts so that they can actually stand upright, leaving part of the rhizome exposed.
Water requirement: Make sure you water the wasabi plants well at planting and then regularly after this. Misting the plants will also help to keep the plant cool. Be very careful not to overwater as the wasabi plants don’t tolerate waterlogged conditions.
Temperature and humidity requirement: One of the most important considerations for growing wasabi plant is that it tolerates only a narrow temperature range, preferring constant temperatures of forty-five to seventy-five degrees Fahrenheit.
Furthermore, temperatures below freezing or that is above eighty degrees Fahrenheit can kill the wasabi plants, so these extremes should be avoided as much as possible. Most coastal locations like the Pacific Northwest provide the suitably cool, temperate weather for growing wasabi plants. Planting the wasabi in containers means you can move the wasabi plants if the thermometer suddenly gets too high or too low.
If the leaves of the Wasabi plants get droopy or wilted you can move the Wasabi plants to shade and mist them a bit.
Varieties of Wasabi
Wasabi has different cultivars which include;
- The ‘Daruma’ variety: This particular variety is more tolerant of high temperatures than most varieties.
- The ‘Fuji Daruma’ variety: The Fuji Daruma are fast-growing variety and they are ready to harvest in the same year if it is planted.
- The ‘Green Thumb’ variety: This variety is really a good choice for edible leaves.
- The ‘Sanpoo’ variety: This particular variety was developed to grow well in poor soils.
- The ‘Mazuma’ variety: The ‘Mazuma’ variety is a slow-growing variety that takes up to 3 years for the roots to mature.
How to Harvest Wasabi
Actually, you won’t be able to harvest the rhizomes of most of the wasabi plants until the second year, so it is very important to care for them attentively. The wasabi plants will be mature enough for pulling within 15 months to 2 years. Nevertheless, the wasabi plants will begin producing leaves within about 8 weeks, so you can enjoy the leafy bounty of your wasabi plants while you wait for the mature stalks. It’s actually good to harvest these leaves in other to keep the plants neat and healthy.
After your first harvest you can let the wasabi plant grow more leaves and harvest them every six to eight weeks. If you cannot eat them all or give them to friends, the leaves can easily be blanched and frozen like any other greens, or you can make a pesto-like sauce for pasta and rice and then freeze it.
The wasabi plants stems can also be frozen, but they are best when eaten fresh. The stems are crunchy and they make a good addition to stir-fry dishes or salads.
Make sure you remove any wilted leaves that don’t perk up after misting. This can really help to avoid any spread of disease or powdery mildew on the plant.
Propagating Wasabi Plants
The Wasabi plant can easily be propagated from seed or from offshoots, but in practice most people normally buy new transplants once the old plants are fully harvested. If you do want to attempt propagation you can snip off some of the little offshoots that appear at the base of a mature plant and then plant them in a 50:50 mixture of sand and compost. In about 2 months they should develop sufficient roots to be transplanted into the garden or into containers.
The wasabi plant seeds are difficult to germinate, which makes it hard to find, even from most commercial suppliers.
Pest and Disease Control
Actually some pests may be a problem to your wasabi plants. Wasabi plant is in the Brassica family and so any bugs that love to eat broccoli or cabbage, such as cabbage worms, will also enjoy munching on the wasabi plant.
You can easily remove slugs by hand, and also aphids can be removed with a steady stream of water or a soft cloth. Just make sure a cool temperature and shady conditions are maintained as this will really help to deter pests. The uses of insecticidal soaps are not recommended for wasabi plant.
If any fungal disease is present on the wasabi plant you can use copper spray or baking soda spray.