Hardy Brassica & Stem-Bulbs
The Hardy Brassica & Stem-Bulb group focuses on swollen-stem and root vegetables that provide the high-density protective compounds of the cabbage family without the high levels of oxalates 1,2. Oxalates are compounds that can interfere with mineral absorption in the gut 2. These vegetables are exceptional sources of Vitamin C and
Vitamin K, supporting immune function and bone mineralisation 3,4. Bone mineralisation is the process by which the body builds strong, dense bone tissue 4.
Nutrition & Ethics
Summary
The Unity Score given below measures how effectively a food can be produced using open-source, decentralised technology—such as 16 storey buildings with 8 subterranean storeys of vertical farms, or subterranean hybrid systems—to ensure every global citizen has local access to essential nutrition 1,14.
A high score indicates that the brassica or stem-bulb can be grown in urban centres worldwide using aeroponic rows or exterior living walls, removing the “environmental footprint” of global shipping and allowing for the rewilding of traditional agricultural land 1,14. Foods with lower Unity Scores are those best suited to subterranean or hybrid production systems that, while highly nutrient-dense, require slightly more physical space or specialised root support to reach full maturity and yield 1,17.
1. The Hardy Brassica & Stem-Bulb League Table
Strictly sorted in descending order by Nutrient Density (Nutrient Aggregate) and Vitamin concentration.
| Rank | Brassica or Stem-Bulb | Nutrient Density | Best for | Vegan Nutritional Superpower |
| 1 | Mizuna/Tatsoi | ⭐⭐⭐⭐⭐ 1,4 | Bone Architecture 3. | World-Leading Vitamin K & Calcium 4. |
| 2 | Radishes | ⭐⭐⭐⭐⭐ 1,3 | Rapid Vitamin Hit 5. | Highest Vitamin C-to-Calorie Ratio 3. |
| 3 | Moringa Sprouts | ⭐⭐⭐⭐⭐ 1,4 | Living Multivitamin 15. | Peak Vitamin A & High Arginine 6. |
| 4 | Baby Mustard | ⭐⭐⭐⭐⭐ 1,4 | Immune Support 4. | Exceptional Vitamin K & Sinigrin 5. |
| 5 | Stem Broccoli | ⭐⭐⭐⭐½ 1,4 | Cellular Defence 5. | Peak Sulforaphane & Vitamin C 3,4. |
| 6 | Salad Turnips | ⭐⭐⭐⭐½ 1,4 | Zero-Waste Eating 1. | “Dual-Output” Vitamin C & Iron 4. |
| 7 | Kohlrabi | ⭐⭐⭐⭐ 1,3 | Low-Oxalate Diets 4. | High Glucosinolates & Vitamin B6 3. |
| 8 | Celeriac | ⭐⭐⭐⭐ 1,3 | Low-Carb Base 8. | Concentrated Vitamin K1 & Phosphorus 3. |
| 9 | Swede | ⭐⭐⭐½ 1,4 | Electrolyte Balance 4. | High Potassium & Slow-Burn Energy 4. |
2. Global Unity & Rewilding Suitability Table
Sorted by suitability for decentralised growth and protection of regional ecological uniqueness.
| Rank | Brassica or Stem-Bulb | Unity Score | Rewilding Impact | Why? |
| 1 | Radishes | ⭐⭐⭐⭐⭐ 1,14 | Extreme 14 | Vertical Production; 25-day cycle on living walls 1. |
| 2 | Mizuna/Tatsoi | ⭐⭐⭐⭐⭐ 1,14 | Extreme 14 | Vertical Production; non-shading rosette shape 14. |
| 3 | Moringa Sprouts | ⭐⭐⭐⭐⭐ 1,1 | Very High 14 | Vertical Production; thrives in stacked trays/darkness 1. |
| 4 | Baby Mustard | ⭐⭐⭐⭐½ 1,14 | High 14 | Vertical Production; wind-hardy urban workhorse 18. |
| 5 | Kohlrabi | ⭐⭐⭐⭐½ 1,14 | High 14 | Vertical Production; bulb sits above roots 14. |
| 6 | Stem Broccoli | ⭐⭐⭐⭐ 1,17 | High 14 | Hybrid Production; upright habit for stacked rows 1. |
| 7 | Salad Turnips | ⭐⭐⭐⭐ 1,17 | High 14 | Hybrid Production; dual leaf-and-root output 1. |
| 8 | Celeriac | ⭐⭐⭐ 1,17 | Very High 13 | Hybrid Production; needs support for heavy bulbs 16. |
| 9 | Swede | ⭐⭐⭐ 1,17 | Extreme 13 | Subterranean Production; thermal ballast for walls 17. |
3. Texture & Phytochemical Composition Cheat Sheet
Technical metrics for nutrient substrates. Strictly sorted by Land-Use Velocity (the speed and density at which a crop clears the vertical hectare to allow for global rewilding). Ratings are strictly internal to each production method.1
| Brassica or Stem-Bulb | Primary Substrate | Functional Texture | Primary Phytochemicals | Traditional Land Use (Field vs Field) | Vertical Land Use (Stack vs Stack) |
| Radishes | Water/Lignin | Sharp/Snap | Anthocyanins 5 | ⭐⭐ (Low mass per cycle) | ⭐⭐⭐⭐⭐ (Fastest turnover) |
| Mizuna/Tatsoi | Soft Fibre | Delicate/Crunchy | Kaempferol 9 | ⭐ (High waste/pests) | ⭐⭐⭐⭐⭐ (Hyper-stackable) |
| Moringa Sprouts | Young Protein | Tender/Nutty | Quercetin 15 | ⭐ (UK climate failure) | ⭐⭐⭐⭐⭐ (Minimal light/space) |
| Baby Mustard | Cellulose Stem | Peppery/Succulent | Sinigrin 5 | ⭐⭐ (Seasonal limit) | ⭐⭐⭐⭐½ (Wind-hardy/fast) |
| Kohlrabi | Starchy Stem | Crisp/Apple-like | Glucosinolates 5 | ⭐⭐⭐ (Solid density) | ⭐⭐⭐⭐½ (Above-root growth) |
| Stem Broccoli | Lignin/Spear | Meaty/Firm | Sulforaphane 5 | ⭐⭐⭐ (Decent cycle) | ⭐⭐⭐⭐ (Upright habit) |
| Salad Turnips | Pectin Root | Buttery/Crunchy | Lutein 9 | ⭐⭐⭐ (Good mass) | ⭐⭐⭐⭐ (Dual leaf/root) |
| Celeriac | Dense Root | Nutty/Dense | Apigenin 11 | ⭐⭐⭐⭐ (High storage mass) | ⭐⭐⭐ (Slow/Heavy) |
| Swede | Slow-Burn Mash | Velvety/Earthy | Glucobrassicin 5 | ⭐⭐⭐⭐⭐ (Massive yield) | ⭐⭐⭐ (Slow/Bulky) |
Rewilding Insight1
- Swede (Rutabaga) is a Traditional Legend (⭐⭐⭐⭐⭐) because it produces more raw biomass and calories per horizontal hectare than almost any other hardy brassica. However, it is a Vertical Amateur (⭐⭐⭐) because its 100-day occupancy limits the number of times a vertical “storey” can be cleared for rewilding.
- Radishes are a Traditional Under-performer (⭐⭐) because they produce very little calorie mass per cycle in a field. Yet, they are Vertical Kings (⭐⭐⭐⭐⭐) because their speed allows for 12 annual “land-clearing” events in an 8-storey facility.
Sources & Endnotes (Introduction Section) – please see the References & Bibliography section for full details of all sources:
- Journal of Food Composition and Analysis — Phytochemical profiles of Brassica vegetables.
- Clinical Nutrition — Oxalate content in root vs leafy vegetables and mineral bioavailability.
- Journal of Agricultural and Food Chemistry — Micronutrient density in swollen-stem cultivars.
- Nutrients — The role of Vitamin K and Vitamin C in skeletal mineralisation.
Sources & Endnotes (Nutrition & Ethics Section) – please see the References & Bibliography section for full details of all sources:
1 Google AI internal knowledge.
2 Throughout this audit, each food’s nutrient content has been compared to the Reference Daily Intakes (RDIs) of different nutrients, essential fats and amino acids for 21-24 year old females. These were based on data from the World Health Organisation (WHO), the USDA Dietary Guidelines, and the UK Scientific Advisory Committee on Nutrition (SACN). For full details, visit: https://naturalhuman.co.uk/reference-intakes/. These values were selected solely as a standardised, fixed benchmark to calculate and compare the exact percentage of nutrients provided by different foods per portion. Using a single baseline like this allows for an objective, side-by-side comparison of individual foods’ nutritional profiles; however, these targets are not universally applicable & must not be considered to be a recommendation.
3 USDA FoodData Central – Analytical profiles for Brassicas and Roots: usda.gov.
4 British Nutrition Foundation – Vitamin K, C, and Bone Health stats: nutrition.org.uk.
5 ScienceDirect – Glucosinolates, Sinigrin, and Sulforaphane in Brassicaceae: sciencedirect.com.
6 Amino Acid Profiles of Leafy and Root Brassicas: nutritionvalue.org.
7 Journal of Food Science – Anti-nutritional factors and mitigation: wiley.com.
8 Kidney Care UK – Oxalate and mineral absorption in vegetables: kidneycareuk.org.
9 Journal of Agricultural and Food Chemistry – Carotenoids and Flavonoids: acs.org.
10 Coeliac UK – Naturally gluten-free vegetable audits: coeliac.org.uk.
11 Molecules – Phytochemical Diversity in Apium and Brassica: mdpi.com.
12 Allergy UK – Cross-reactivity in the Mustard family: allergyuk.org.
13 Our World in Data – Land Use and Environmental Footprints: ourworldindata.org.
14 Frontiers in Plant Science – Physical limits of vertical and aeroponic farming: frontiersin.org.
15 International Journal of Food Science – Phytochemicals in Moringa: hindawi.com.
16 Water Footprint Network – Water use of hardy vegetable crops: waterfootprint.org.
17 International Journal of Agronomy – Aeroponic growth rates for roots: hindawi.com.
18 RHS – Growing Hardy Brassicas in the UK: rhs.org.uk.
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