Raphanus sativus.
A variety developed to reproduce in the vegetable garden the explosive heat of Japanese wasabi — that volatile pungency that rises into the nose rather than to the tongue, that clears the sinuses in two seconds then disappears as fast as it came. The sleight of hand rests on an elegant botanical fact: authentic wasabi (Eutrema japonicum), horseradish (Armoracia rusticana) and radish (Raphanus sativus) all belong to the same great Brassicaceae family and produce, in varying degrees, the same molecule responsible for that sensation — allyl isothiocyanate. Authentic wasabi being extremely expensive and difficult to cultivate, almost all of the "wasabi" served in restaurants is actually horseradish dyed green — this selected radish offers a solution at once more accessible, fresher and more authentic.
Round or slightly elongated roots 3 to 5 cm, pale green skin tinged with white, pure white flesh, crunchy and juicy. Far from the mild pink radish you absent-mindedly slice into a salad — here, it's a sensory bomb. Excellent finely grated on homemade raw fish or sashimi, mixed with a little soy sauce as a condiment, whisked into a vinaigrette with lemon and honey for a near-medicinal sinus-clearing effect, pickled in Japanese style (tsukemono) with salt and sugar, or simply crunched raw for thrill-seekers. The tops are also edible and carry the same hot note, in more measured form.
Grower's tip: Like all radishes, it's a fast crop that loves cool weather. Direct-sow in place as soon as the soil can be worked, in successive rows every 10-14 days to stretch the harvest from June to frost. Loose, stone-free, moderately rich soil — too much nitrogen gives plenty of leaves and disappointing roots. Don't let it overshoot maturity in the garden — an over-mature radish turns fibrous, hollow and unpleasantly pungent (yes, even more). For particularly intense roots, grow in cool weather; summer heat tends to soften the heat and accelerate bolting.
- Open-pollinated. Annual to biennial depending on conditions. Insect-pollinated; crosses with other radishes nearby — isolate for seed saving.
- Top height: 15 to 25 cm.
- Maturity: 25 to 35 days.
- Exposure: full sun; part shade accepted in summer.
- Loose, stone-free, moderately rich soil. Thin to 5 cm.
- Direct-sow as soon as the soil can be worked (April in Québec), in successive rows every 10-14 days through late August. Tolerates light fall frosts.
