How to Grow Early Tomatoes with Wall of Water: Jump-Start Your Harvest by 4-6 Weeks
Intro for growing early tomatoes with wall of water
A Wall of Water (also called a season extender or water teepee) is an ingenious gardening tool that allows you to plant tomatoes weeks before your last frost date. These protective cylinders consist of connected plastic tubes filled with water that surround young tomato plants. The water absorbs heat during the day and releases it at night, creating a microclimate that can withstand temperatures as low as -6°C (20°F). By using this method, gardeners in temperate regions can harvest tomatoes up to 6 weeks earlier than traditional planting methods. This technique is particularly valuable in areas with short growing seasons or for gardeners eager to enjoy the first sun-ripened tomatoes of the season.
When to plant early tomatoes with wall of water
With a Wall of Water, you can plant tomatoes 4-6 weeks before your region’s last expected frost date. In most temperate regions, this means planting in late March to mid-April rather than waiting until May. The soil temperature inside the Wall of Water will be significantly warmer than exposed soil, but ideally, you want the soil temperature to reach at least 10°C (50°F) before planting. The Wall of Water will protect your tomato plants from late frosts, cold winds, and even light snow, extending your growing season considerably at both ends.
Best time to plant early tomatoes with wall of water

In cool temperate regions (UK, US Zones 4-6), set up your Walls of Water in mid to late March and plant tomato seedlings in early to mid-April, about 4-6 weeks before your last frost date. In warmer regions (US Zones 7-9), you can set up in February and plant by early March. Always transplant seedlings rather than direct sowing with this method. For maximum effectiveness, set up the Walls of Water 1-2 weeks before planting to pre-warm the soil. Remove the protectors when nighttime temperatures consistently stay above 10°C (50°F) and all danger of frost has passed.
Best early tomato varieties to grow with wall of water
- Early Girl – Reliable producer that matures in just 50-60 days with medium-sized fruits perfect for slicing.
- Stupice – Czech heirloom that’s extremely cold-tolerant and produces sweet, tangy fruits in just 52 days.
- Sungold – Intensely sweet cherry tomato that’s relatively cold-hardy and produces abundant early harvests.
- Sub-Arctic Plenty – Ultra-early variety developed for short seasons, producing in just 45 days.
- Oregon Spring – Parthenocarpic variety that sets fruit even in cool weather, perfect for coastal and northern gardens.
- Glacier – Compact determinate plant ideal for containers with sweet, tangy fruits in just 55 days.
- Siberian – Extremely cold-tolerant heirloom that thrives in cool conditions where other tomatoes struggle.
How to plant early tomatoes with wall of water
Materials needed:
- Wall of Water protectors (one per plant)
- Tomato seedlings (hardened off but not too large)
- Compost or well-rotted manure
- Balanced organic fertilizer
- Watering can with spout
- Bucket for filling Wall of Water
- Garden trowel
- Black plastic (optional, for warming soil)
Step-by-step planting:
- Choose a sunny location with well-draining soil that receives at least 6-8 hours of direct sunlight.
- Prepare the soil 1-2 weeks before planting by incorporating 2-3 inches of compost and a handful of balanced organic fertilizer.
- Optional: Cover the planting area with black plastic for 1-2 weeks to pre-warm the soil.
- Set up the Wall of Water by placing it flat on the ground, then filling each tube halfway with water using a watering can with a spout.
- Once all tubes are partially filled, carefully pull the Wall of Water upright to form a teepee shape around the planting spot.
- Fill the tubes completely with water, ensuring the structure is stable and evenly balanced.
- Allow the setup to sit for 1-3 days to warm the soil inside the teepee.
- Dig a planting hole in the center of the teepee, slightly deeper than the root ball of your seedling.
- Plant the tomato seedling, burying it up to the first set of true leaves to encourage additional root growth.
- Water thoroughly but gently to avoid disturbing the roots or Wall of Water structure.
How to grow early tomatoes with wall of water
Tomatoes inside Walls of Water need consistent care for best results. Ensure they receive full sunlight for at least 6-8 hours daily. The water-filled tubes will moderate temperature, but you’ll still need to water the plants when the top inch of soil feels dry. Initially, water carefully to avoid splashing soil onto the plants. Once established, water deeply 1-2 times per week rather than frequent shallow watering.
Apply a balanced organic fertilizer every 2-3 weeks once plants show strong growth. When nighttime temperatures consistently stay above 10°C (50°F), usually 3-4 weeks after planting, carefully remove the Wall of Water by emptying each tube and lifting it straight up. At this point, apply a 2-3 inch layer of organic mulch around the plants to retain moisture and suppress weeds.
For container growing with Walls of Water, use a minimum 5-gallon (19-liter) container with drainage holes. The same principles apply, but container plants may need more frequent watering. Install stakes or cages immediately after removing the Wall of Water to support the rapidly growing plants.
Caring for early tomatoes with wall of water
While the Wall of Water is in place, monitor soil moisture carefully as the enclosed environment can dry out quickly on sunny days. Check for condensation inside the teepee – excessive moisture can encourage fungal diseases. Ensure adequate ventilation by slightly separating the tops of the tubes on very warm days.
Watch for early signs of pests like aphids or whiteflies, which may be attracted to the warm, protected environment. A gentle spray of insecticidal soap can control these if needed. Once the Wall of Water is removed, remain vigilant for late blight (dark spots on leaves and stems) and apply copper fungicide preventatively in humid conditions.
Harvest tomatoes when they’ve reached full color and yield slightly to gentle pressure. Early-season tomatoes grown with this method can be harvested from late May to early June in most temperate regions. Store harvested tomatoes at room temperature, never in the refrigerator, to maintain best flavor.
Understanding bolting in early tomatoes with wall of water
Unlike leafy greens, tomatoes don’t bolt in the traditional sense. However, they can experience stress responses if temperatures inside the Wall of Water get too high. If daytime temperatures exceed 32°C (90°F), the enclosed environment can become too hot, causing flower drop and poor fruit set.
To prevent heat stress, partially open the top of the Wall of Water on hot, sunny days to allow heat to escape. You can also provide partial shade during the hottest part of the day if necessary. If plants show signs of heat stress (wilting despite moist soil, yellowing leaves), remove the Wall of Water earlier than planned and provide temporary shade until the plant recovers.
Why does early tomatoes with wall of water turn bitter?
- Temperature fluctuations – Extreme swings between day and night temperatures can affect flavor; maintain more consistent temperatures by ensuring Walls of Water are fully filled.
- Insufficient sunlight – Condensation on the inside of Walls of Water can reduce light penetration; clean if necessary or remove earlier if plants appear leggy.
- Uneven watering – Stress from inconsistent moisture can cause bitter compounds to develop; maintain even soil moisture.
- Nutrient imbalance – Too much nitrogen can reduce sweetness; use a balanced fertilizer with adequate phosphorus and potassium.
- Harvesting too early – Tomatoes need to fully ripen on the vine for best flavor; be patient and wait for complete color development.
Companion planting for early tomatoes with wall of water
While your tomatoes are protected by Walls of Water, companion planting is less critical. However, once you remove the protectors, these companions can be planted nearby:
- Basil – Repels flies and mosquitoes while improving tomato flavor and growth.
- Marigolds – Deter nematodes and other soil pests with their root secretions.
- Nasturtiums – Act as trap crops for aphids, keeping them away from your tomatoes.
- Carrots – Their root growth pattern complements tomatoes without competing for nutrients.
- Garlic or onions – Repel many tomato pests with their strong scent.
Avoid planting tomatoes near:
- Potatoes – Can transmit blight to tomatoes and compete for similar nutrients.
- Brassicas (cabbage, broccoli, etc.) – Inhibit tomato growth through chemical interactions.
- Corn – Attracts tomato fruit worm and competes for nutrients.
Seasonal calendar
- February – Start tomato seeds indoors (6-8 weeks before planned outdoor planting).
- March – Prepare planting sites and set up Walls of Water to pre-warm soil (cool regions).
- Early April – Plant hardened-off seedlings inside Walls of Water (cool regions).
- Late April/Early May – Monitor for heat stress on warm days; ventilate if needed.
- Mid-May – Remove Walls of Water when night temperatures stay above 10°C (50°F); install stakes or cages.
- Late May/Early June – Begin harvesting early varieties; apply organic mulch.
- June-September – Regular harvesting, watering, and feeding.
- October – Clean and store Walls of Water for next season after final harvest.
Note: For warmer regions (Zones 7-9), advance this schedule by 4-6 weeks. For cooler regions (Zones 3-4), delay by 2-3 weeks.
Problems & solutions
Problem | Quick Fix |
---|---|
Wall of Water keeps collapsing | Fill tubes more evenly; use a circular support inside until established |
Excessive condensation inside | Ventilate top slightly during daytime; wipe interior if severe |
Plants wilting despite moist soil | Heat stress – ventilate top or remove Wall of Water earlier than planned |
Seedlings growing too tall/leggy | Insufficient light – clean walls or remove protection earlier |
Frost damage despite protection | Ensure all tubes are fully filled with water; add second Wall of Water in extreme conditions |
Poor fruit set after removal | Tap flowers gently at midday to encourage pollination; use blossom set spray |
Algae growing in water tubes | Add a few drops of hydrogen peroxide to water when filling; not harmful to plants |
Common questions about growing early tomatoes with wall of water
How often should I water tomatoes in a Wall of Water?
Check moisture every 2-3 days by inserting your finger 1 inch into the soil. The enclosed environment retains moisture longer than exposed plants, so water only when the soil feels dry at this depth.
Can I reuse Walls of Water for multiple seasons?
Yes, with proper care. After the growing season, empty, clean with mild soap, dry completely, and store flat in a dark location. Most units last 3-5 seasons with proper care.
How tall should tomato seedlings be before planting in a Wall of Water?
Ideal seedlings should be 6-8 inches (15-20 cm) tall with a sturdy stem and at least 2-3 sets of true leaves. Avoid using overly tall or leggy seedlings.
Can I use Walls of Water for fall planting to extend the season?
Yes, Walls of Water can protect plants from early fall frosts, potentially extending your harvest by 3-4 weeks. Install them when nighttime temperatures begin dropping below 10°C (50°F).
How much earlier will I get tomatoes using this method?
In most temperate regions, you can expect to harvest tomatoes 4-6 weeks earlier than traditional planting methods, depending on the variety and your local climate.
What’s the minimum container size for using a Wall of Water?
Use containers at least 5 gallons (19 liters) in volume and 12 inches (30 cm) in diameter to accommodate both the plant’s root system and the Wall of Water structure.
Can I use Walls of Water for other warm-season vegetables?
Yes, they work well for peppers, eggplants, and even cucumbers. The principle remains the same—they create a protective microclimate for tender plants.