Why Grow Tomatoes in RDWC?
Tomatoes are the most popular crop for UK hydroponic growers — and RDWC is one of the best systems for growing them. The constant supply of oxygenated, nutrient-rich water at the root zone drives faster vegetative growth and heavier fruiting than soil, often producing 2–3x the yield in the same space.
With a MUSHROOMTEC RDWC Bundle, you can grow 4–8 tomato plants in a single recirculating system managed from one central reservoir.
Choosing the Right Tomato Variety
Not all tomato varieties are equally suited to RDWC. Indeterminate (vining) varieties perform best as they continue growing and fruiting throughout the season:
- Sungold — sweet cherry tomatoes, extremely prolific, excellent for RDWC
- Gardener's Delight — reliable UK favourite, consistent yields
- Beefsteak varieties — large fruit, longer to mature but impressive yields in RDWC
- Roma — meaty, low-moisture tomatoes ideal for cooking and sauces
Avoid determinate (bush) varieties in RDWC — they stop growing after fruiting and don't make efficient use of the system.
System Setup for Tomatoes
Tomatoes develop large root systems and benefit from the full 20L bucket volume. For 4–8 plants, we recommend:
- 4-Bucket RDWC Bundle for 4 plants in a 1.2m x 1.2m space
- 6-Bucket Bundle or 8-Bucket Bundle for larger grows
- A 25W Submersible Pump for 8-bucket systems to ensure adequate circulation
Nutrient and Water Management
Tomatoes are heavy feeders and require careful nutrient management through their growth stages:
- Seedling/early veg: EC 1.2–1.6 mS/cm, pH 5.8–6.0
- Vegetative growth: EC 1.6–2.0 mS/cm, pH 5.8–6.0
- Flowering: EC 2.0–2.4 mS/cm, pH 6.0–6.2 (slightly higher pH improves calcium uptake)
- Fruiting: EC 2.2–2.8 mS/cm, pH 6.0–6.2
Check pH and EC daily — tomatoes are heavy drinkers and the reservoir level and nutrient concentration will change quickly during peak growth. Top up with pH-adjusted water daily and do a full reservoir change every 7–10 days.
Training and Support
Indeterminate tomatoes will grow tall — often 1.5–2m or more in a hydroponic environment. Use bamboo canes or a trellis system to support the main stem. Remove suckers (side shoots growing between the main stem and branches) regularly to direct energy into fruit production rather than excessive foliage.
Common Tomato Problems in RDWC
- Blossom end rot: Calcium deficiency, usually caused by pH being too low. Raise pH to 6.0–6.2 and ensure adequate calcium in your nutrient solution.
- Yellowing lower leaves: Normal as the plant matures, but if spreading rapidly, check pH and EC.
- Slow fruit set: Pollination issue. Gently shake flowering trusses daily or use a small electric toothbrush on the flower stems to simulate wind pollination.
Ready to Start Your Tomato Grow?
Browse our full range of RDWC Bundle Offers and Accessories to build the perfect tomato growing setup. Our systems ship across the UK and are ready to fill and grow from day one.