Rose de Berne is a cherished heirloom tomato variety, renowned for its distinct flavor and visual appeal. This article provides a comprehensive guide to understanding, cultivating, and enjoying these unique tomatoes.
Understanding Rose de Berne
The Rose de Berne tomato is an heirloom variety originating in Switzerland, specifically from the city of Bern, and is also popular in France and Germany.
This indeterminate variety produces plants that continue to grow and bear fruit throughout the season until halted by cold weather. Rose de Berne typically yields medium-sized, round, or slightly flattened fruits. These tomatoes are characterized by their smooth, rosy pink skin, sometimes displaying a subtle bluish hue, and usually weigh between 180 to 240 grams, or about 4 to 8 ounces.
Flavor Profile and Culinary Applications
Rose de Berne tomatoes are celebrated for their exceptional flavor, often described as sweet and rich with well-balanced, low acidity. The flesh inside is typically juicy and meaty. Their tender texture makes them a favorite.
Their delicate nature and soft, thin skin make them particularly well-suited for fresh consumption, such as sliced for sandwiches or added to salads. While best enjoyed fresh and soon after harvest, their juicy and meaty consistency also makes them suitable for light sauces or soups.
Cultivating Rose de Berne
Planting
Start Rose de Berne seeds indoors 5 to 8 weeks before the last anticipated frost. Sow seeds 0.5 to 1 cm deep in pots, maintaining a temperature between 16 and 20°C for germination. Once seedlings are around 10 cm tall, harden them off by gradually exposing them to outdoor conditions. Transplant outdoors after the danger of frost has passed, ensuring night-time temperatures are consistently above 10°C. Plant seedlings at least 50 cm apart, burying the stem up to the first leaves to encourage strong root development.
Soil
Ideal soil for Rose de Berne tomatoes is well-drained and rich in organic matter. While they can adapt to various soil types, consistent moisture is beneficial. A soil pH around 6-6.5 is generally suitable for tomato growth. Tomatoes are considered “hard feeders,” indicating they require regular nourishment from the soil.
Light
Rose de Berne plants require full sun exposure for optimal growth and fruit production. If plants have been started indoors, gradually acclimate them to direct sunlight to prevent sunburn. In regions with intense summer heat, some shade cloth can be beneficial to protect vines and fruit from scorching.
Water
Consistent and even watering is crucial for Rose de Berne tomatoes, as irregular water supply can lead to issues like fruit cracking or blossom end rot. They have a medium to high water requirement. Water the soil directly, avoiding wetting the leaves, which can promote fungal diseases.
Fertilizing
Tomatoes are considered “hard feeders,” requiring regular nourishment. Once plants are larger and begin to set fruit, apply a bloom booster or a balanced fertilizer. Specific feeding schedules should follow product instructions, and consistency throughout the growing season will support continuous production.
Support
As an indeterminate variety, Rose de Berne tomatoes will continue to grow tall and produce fruit throughout the season, necessitating a strong support system. Staking or caging is essential to keep the heavy vines off the ground, promoting air circulation and preventing disease. Tying plants to struts or ribbons and regularly pinching out suckers directs the plant’s energy towards fruit development.
Addressing Common Growing Issues
Rose de Berne tomatoes, like many heirloom varieties, can face specific challenges. Irregular watering can cause fruit cracking, where the skin splits, or blossom end rot, which appears as a dark, sunken spot on the bottom of the fruit. Maintaining consistent soil moisture is the primary preventative measure for these issues.
While generally robust, Rose de Berne can be susceptible to common tomato pests and diseases. Hornworms can be hand-picked from plants, and aphids can often be dislodged with a strong stream of water. For diseases like blight, which can manifest as lesions on leaves and stems, preventative measures include ensuring good air circulation around plants and protecting them from rain.
Harvesting and Preserving Seeds
Rose de Berne tomatoes are ready for harvest when they develop their rosy pink color and feel firm but slightly yielding. Due to their soft, thin skin, these tomatoes are best picked when ripe and consumed relatively quickly, as they do not store for extended periods.
To save seeds for future planting, select healthy, fully ripe tomatoes from robust plants. Scoop out the seeds along with their gelatinous pulp into a jar. Add a small amount of water to cover the seeds and allow them to ferment for 3 to 5 days, loosely covering the jar. This fermentation process breaks down the gel coating that inhibits germination and helps eliminate some seed-borne pathogens.
After fermentation, good seeds will sink to the bottom. Rinse the seeds thoroughly to remove any remaining pulp or mold, then spread them in a single layer on a non-stick surface like a glass plate or parchment paper to dry completely. Once thoroughly dry, which may take several days to two weeks, store the seeds in a labeled envelope or airtight container in a cool, dark, and dry place. Properly stored, Rose de Berne seeds can remain viable for up to five years.