Hi everyone,
After Joseph Lofthouse recently shared my post about Blossom End Rot (BER) on Facebook with a note “well said,” I wanted to bring the broader context of this topic to the forum. In my location (Otín, Czech Republic, 560 m a.s.l., short season, cold nights, high slug pressure), I don’t treat BER as a failure, but as a crucial selection tool within my landrace project.
To be completely honest and pour some ashes on my head—my project is currently in a state of chaotic delay. My personal motto for this season is “Always Behind Schedule.” I just finished planting the last of my tomatoes yesterday! The 12-meter bed is a massive logistical beast to build alone, and it is still a work in progress. I still need to burn more biochar for the top layer, collect more red water bottles, and finish moving the heavy stones behind the western pathway. But this rough reality makes the evolutionary pressure even more interesting.
You can see this in the attached photos: the biochar mulch and red bottles are only finished on the first 3 meters, with empty starter pots still scattered around from last night’s planting marathon.
To run this high-pressure polycross pool of 50+ tomato lines under these delayed conditions, I am using a systemic infrastructure that forces the plants to rely on biological symbiosis to solve both the calcium-drought bottleneck and my scheduling delays, combined with radical genetic mixing.
1. The Bed Architecture & Moisture Reservoir
To compel deep root architecture, the bed is excavated 50 cm deep and sunken 10 cm below the pathways.
- The Bottom Layer (50 cm depth): A 12 cm layer of biochar, charged for a month in a concentrated leachate of ground elder (Aegopodium podagraria). This creates a massive, stable nutrient and deep-moisture sponge in our clay-stone subsoil. (Due to my delays, only part of the bed has the fully charged biochar so far; the rest was heavily soaked with water and organic elder residues, and I will have to re-dig and finish it properly this autumn).
- The Thermal Battery: Surface biochar for immediate soil heating, a western stone wall, and three rows of red water PET bottles to buffer extreme night temperature drops (both currently being expanded as I catch up).
2. The Mycorrhizae Pipeline & Planting Geometry
BER is fundamentally a calcium transport issue caused by erratic water movement. In a zero-irrigation system, roots alone cannot reach the micro-pores containing tightly bound water and calcium.
- During pricking out and final transplanting, all seedlings received a heavy inoculation of symbiotic mycorrhizae (Symbivit).
- The Spacing Web: Plants are spaced 40 cm apart in a zig-zag double row, planted diagonally and deeply, with roots pointing north. This 40 cm zig-zag spacing keeps the canopy airy enough for single-truss training, yet remains close enough for the mycorrhizae to bridge all individual root systems into a single, collaborative “information web” and nutrient pipeline.
3. Maximizing Polycross Diversity & Counter-Directional Layout
To achieve maximum genetic mixing within this zig-zag double row, the planting order is strictly structured:
- Row 1 (from North): Ordered from the earliest maturing varieties to the latest.
- Row 2 (from North): Ordered from the latest maturing varieties to the earliest.
This counter-directional layout ensures that early and late genetics are constantly forced into close proximity for pollen exchange across the zig-zag pattern.
Here is the 2026 “survivor” list making up this diverse grex pool:
Altai Orange, Artisan Blush Tiger, Artisan Green Tiger, Artisan Pink Tiger, Atomic Grape, Black Krim, Boloto, Bajaja, Brandywine, Brandywine Black, Bubble Gum, Cranberries in Sugar, Dívčí prs, Divoké havajské (Wild Hawaiian), Evergreen, Geranium Kiss, German Gold, Glacier, Goldmarie, Green Moldovan, Herodes, Lida Ukrainen, Malvika Orange, Matt’s Wild Cherry, Midas, Mila, Nature’s Riddle, Oaxacan Jewel, Purple Calabash, Red Punk, Rio Grande, Ruthje, San Marzano 3, Sarajev, Siberian, Sleeping Lady, Sonnenherz, Stupické polní, Taiko, Tajga, Tomastrong F1 (inter-species hybrid with S. habrochaites), Valouny, Vejce ptáka ohniváka, Wapsipinicon Peach, Yellowstone.
4. Radical Nitrogen Regulation & The Water Cut-off
Too much nitrogen stimulates rapid vegetative growth, which dilutes calcium distribution, triggers BER, and invites late blight (Phytophthora infestans).
- Pre-drying Biomass: Both the ground elder used for charging the biochar and the grass used for top-mulching are thoroughly dried before application. This pre-drying process forces the excess volatile nitrogen to escape into the atmosphere. Because the dried ground elder is nitrogen-depleted, the biochar becomes purely loaded with mineral nutrients without the risk of nitrogen overload, ensuring the plants don’t produce excessive leaf mass.
- The Water Cut-off: I irrigate heavily for the first 14 days post-transplant, adding a molasses solution (450g per 9L) to explosively jumpstart the soil microbiome and fungal network. After 14 days, the surface biochar is bagged, the bed is sealed with cardboard and a thick layer of dried grass, and all irrigation stops permanently.
5. Selection Criteria: The One-Truss Hard Filter & Promiscuity
To beat our short season, I train the entire pool to a single truss (one-vijan), aggressively culling late flowers. This creates an intense physiological pressure cooker.
I actively select for promiscuous flower anatomy (large, open flowers with exserted stigmas) to boost cross-pollination. Simultaneously, I apply a brutal negative selection against BER. Plants that fail under this sandwich-bed drought stress are not saved.
An heirloom variety is history—something created in the past and artificially kept static like a clone. A landrace is a selection for the present and the future. By letting this diverse grex cross freely under zero-irrigation, the plants reclaim their wild self-sufficiency. I am not a dictator to them; I am just the selector.
I would love to hear from others practicing dry farming or breeding landrace tomatoes:
- How aggressive is your culling when BER hits your lines during the first severe drought cycle?
- How do your inter-species lines (like S. habrochaites crosses) behave regarding BER compared to pure domestic heirlooms when water is completely cut off?
Looking forward to your insights!
