The Merlot potato is a variety of German origin. It has recently gained popularity among European farmers and consumers due to its excellent qualities. Although it requires careful watering and fertilization, this variety is now widely cultivated in Central and Western Europe. The tubers stand out with their deep red skin and vibrant yellow flesh.
In this article, you will learn how to grow Merlot potatoes, the challenges farmers may face, and how to overcome them.
Table of contents
Origin and Description of the Variety
The Merlot potato is a late-maturing variety developed by German breeders from Nordika Nordring Kartoffelzucht und Vermehrungs GmbH. It was officially registered in the European Union's plant variety database in 2015.
The variety is approved for cultivation in Central and Western Europe, including Germany, France, Belgium, the Netherlands, and Poland.
Key characteristics of the plant are summarized in the table below.
| Parameter | Description |
| Maturity | 80-95 days |
| Plant | Medium height, semi-upright, intermediate type |
| Tubers per plant | 6-10 |
| Weight | 90-140 g |
| Shape | Oval |
| Color | Red skin, deep yellow flesh |
| Leaves | Small, green |
| Flower color | Red-violet |
| Starch content | 14-16% |
| Taste | Excellent (5 out of 5) |
| Culinary type | B/C (moderate to high mealiness) |
| Yield | Average: 190-355 t/ha, maximum: 504 t/ha |
| Marketability | 84-96% |
| Storage stability | 98% |
| Purpose | Table use |
| Resistance | Resistant to potato cancer, golden nematode, and leaf roll virus |
| Transportability | High |
Cultivation Techniques
The Merlot variety is demanding in terms of soil and care. It thrives best in loamy, sandy, or peat soils with good drainage. The plant does not tolerate acidic soil, so a pH test is recommended before planting. The optimal pH range is 5.2-5.7. To reduce acidity, dolomite flour, slaked lime, or chalk can be used. Wood ash helps balance alkaline soils.
Planting Time, Scheme, and Guidelines
Planting usually begins in early or mid-May, when the soil temperature reaches at least +8°C and the air temperature is around +15°C. According to the breeder, pre-sprouting is optional. However, tubers should be treated with a disinfectant solution containing copper sulfate or potassium permanganate, or a commercial product like "Maxim," followed by growth stimulants such as "Epin" or "Zircon" a day before planting.
For those who prefer traditional pre-planting preparation, expose the seed potatoes to sunlight 2-3 weeks before planting. The ideal sprouting temperature is +15…+17°C, and sprouts should appear within two weeks.
In autumn, prepare the field by plowing, harrowing, removing weeds, and enriching the soil with compost. In spring, grow green manure crops (lupine, wheat, flax, peas, rye, or oats) and incorporate them into the soil after a month. Decomposed green manure improves soil structure and suppresses pathogens.
Arrange the rows in a north-south direction to ensure even sunlight exposure.
Plant the tubers 10 cm deep with 35 cm spacing. Row spacing should be 50-60 cm. Add a handful of ash and superphosphate to each hole, then cover with soil without compacting.
Other German potato varieties worth exploring:
Young but promising German potato variety "Krona"
Mid-early, resilient potato variety "Satina"
Mid-early, low-maintenance potato variety "Red Fantasy"
Care Guidelines
Key care practices:
- Watering. Merlot potatoes require consistent moisture. In southern regions, drip irrigation is recommended, while in temperate climates, natural rainfall may suffice. Increase watering during tuber formation, ensuring the soil is moist to a depth of 45-50 cm.
- Weeding and soil loosening. Loosen the soil after each watering and remove weeds promptly.
- Hilling. This practice boosts yield by 30-40%. Cover the stems with soil when they reach 10-15 cm, repeat during flowering, and once more after 2-3 weeks. Water before hilling to facilitate the process.
- Fertilization. Apply fertilizer three times during the growing season. Foliar feeding is particularly effective, as plants absorb nutrients more efficiently through leaves.
The table below outlines a recommended fertilization schedule.
| Application Stage | Fertilizer | |
| I | Active foliage growth | 20 g urea, 20 g "Effekton"/10 L water (500 mL per plant) |
| II | Bud formation | 200 g wood ash, 20 g potassium sulfate/10 L water (500 mL per plant) |
| III | Flowering | 20 g superphosphate, 20 g "Effekton"/10 L water (500 mL for foliar spray) |
Growing Challenges and Solutions
To maximize yield, follow crop rotation rules. Potatoes grow well after carrots, cabbage, lupine, alfalfa, cucumbers, peas, or beans. Avoid planting after tomatoes, eggplants, or peppers due to shared diseases.
Besides traditional planting methods, some growers use barrel cultivation. This technique is ideal for small spaces.
Advantages of barrel cultivation:
- Space-saving;
- No need for weeding or hilling;
- Protection against fungi and pests;
- Reduced risk of tuber rot;
- Lower labor requirements;
- Faster maturation.
Disadvantage — requires careful soil preparation and barrel setup.
Step-by-step process:
- Use metal or plastic barrels (minimum 7 L volume, 30 cm height).
- Remove the bottom and sterilize the inside with boiling water and soda. Paint the exterior in light colors to reduce heat absorption.
- Drill ventilation holes (1 cm diameter) every 10-15 cm.
- Prepare soil mix from compost, turf, and humus (equal parts). Disinfect with potassium permanganate or copper sulfate.
- Place the barrels in a sunny spot. Add a 10 cm layer of soil and compost, then arrange seed potatoes (20 cm apart). Cover with 10 cm of soil.
- When sprouts reach 2-3 cm, add another 10 cm layer of soil. Repeat until the barrel is 1 m high.
- Water 3-4 times during the season.
- Apply nitrogen and potassium after sprouting, then phosphorus after flowering.
- Harvest when foliage yellows (about 3 months after last fertilization). Expected yield: ~1 bag per m².
Diseases and Pests
According to phytopathological studies, Merlot potatoes show moderate susceptibility to late blight in foliage and tubers. Excessive moisture and cool temperatures increase the risk.
Preventive measures:
Control nitrogen levels;- Practice crop rotation;
- Remove weeds and plant debris;
- Treat tubers with potassium permanganate or "Fitosporin";
- Apply potassium-phosphorus fertilizers;
- Spray plants with copper-based fungicides or milk-iodine solution.
If infected, remove affected foliage and treat with "Oxyhom," "Ridomil," Bordeaux mixture, or "Bravo." During tuber formation, use "Alufit" once.
The Colorado potato beetle is the most common pest. Combining chemical and organic methods works best.
Control strategies:
- Manual collection (for small infestations);
- Dusting with birch ash or cornmeal;
- Spraying with sunflower oil (200 mL/10 L water);
- Applying fungicides ("Stop-Beetle," "Ampligo," "TurboPresto");
- Planting repellent flowers (marigolds, calendula, nasturtium);
- Encouraging natural predators (ladybugs, birds).
Wireworms (click beetle larvae) damage tubers by boring holes, leading to rot.
Effective treatments:
- Chemical insecticides ("Aktara," "Prestige," "Diazinon");
- Watering planting holes with potassium permanganate;
- Adding onion peels to planting holes;
- Herbal infusions (nettle, dandelion, coltsfoot).
Harvesting, Storage, and Usage
Harvest in mid-to-late September. Dry tubers in shade for 3-4 days, then sort and discard damaged ones.
Store in a cool, dry place (+2…+3°C, 70-80% humidity). Ideal locations include cellars or insulated balconies. Specialized "balcony storage boxes" with heating are also available.
Merlot potatoes have excellent taste and visual appeal. Their moderate starch content makes them versatile for boiling, frying, roasting, or baking. The flesh does not darken after cutting.
Pros and Cons
Advantages:
- High yield;
- Disease resistance;
- Long shelf life;
- Attractive appearance;
- Excellent taste;
- Good transportability.
Disadvantage — Demanding soil and care requirements.
Farmer Testimonials
Feedback on the Merlot variety is overwhelmingly positive. Farmers appreciate its productivity, quality, and storability, while consumers love its taste.
Thomas, Germany: "I’ve grown many potato varieties over the years, but Merlot stands out. The red skin and yellow flesh are eye-catching, and the flavor is exceptional. It stores well without spoiling."
Sophie, France: "Merlot potatoes require attention to watering and fertilization, but the effort pays off. I fertilize three times and use drip irrigation. The results are consistently excellent."
Conclusion
The Merlot potato is a high-yielding, late-maturing German variety known for its visual appeal, taste, and storage qualities. While resistant to many diseases, it can develop late blight in humid conditions.
Crop rotation, seed treatment, and preventive sprays with copper-based products minimize disease risks. Combining chemical and organic methods effectively controls Colorado potato beetles and wireworms.