The houseplant community is divided over a simple question: should you water from above or below? This debate between bottom watering and top watering isn’t just about preference—each method affects your plants’ root development, soil health, and long-term vitality in fundamentally different ways.
Bottom watering has exploded in popularity recently, with plant parents praising its ability to prevent overwatering and eliminate fungus gnats. Meanwhile, traditional top watering remains the go-to method for its speed and simplicity. So which approach actually delivers better results?
Here’s the truth: neither method is universally superior. The “best” watering technique depends on your specific plants, pot types, and lifestyle. This guide breaks down exactly when to use each method—and why combining both strategies often works best.
Understanding Both Methods
Before comparing benefits and drawbacks, let’s establish exactly what each method involves and how it works.
What is Bottom Watering?
Bottom watering means placing your potted plant in a container of water, allowing it to absorb moisture through drainage holes in the pot’s bottom rather than pouring water on top of the soil.
How it works: Fill a tray, saucer, or sink with 1-2 inches of room-temperature water. Place your plant in the water so drainage holes are submerged (water level should reach about one-quarter up the pot’s height). Leave it for 15-30 minutes while the soil absorbs water through capillary action—the same force that draws water up through a paper towel.
Water molecules are attracted to soil particles more strongly than to each other. This adhesive force pulls water upward through tiny spaces in the soil against gravity, gradually moistening the entire root zone from bottom to top.
You’ll know it’s done when: The top inch of soil feels damp to touch, or the soil surface darkens with moisture. At this point, remove the plant and let excess water drain for 5-10 minutes before returning it to its usual spot.
Critical requirement: Bottom watering only works with pots that have drainage holes. Without these openings, water cannot enter from below.
What is Top Watering?
Top watering is the traditional method where you pour water directly onto the soil surface using a watering can or cup, letting gravity pull moisture down through the pot.
How it works: Slowly pour room-temperature water across the entire soil surface (not just one spot) until water flows freely from the drainage holes at the bottom. This usually takes 1-2 minutes depending on pot size. The downward flow moves through the root zone, with soil particles and roots absorbing moisture as it passes.
The key benefit: This downward movement naturally flushes accumulated salts, minerals, and fertilizer residue through the soil and out the drainage holes—a cleaning action that bottom watering doesn’t provide.
Proper technique matters: Water slowly to prevent runoff across the surface. Distribute water evenly over the entire soil area. Always water until you see drainage—this ensures the entire root ball gets moistened, not just the top layer.
The Comparison: When Each Method Wins
Now that you understand the mechanics, let’s examine when each approach delivers superior results.
When Bottom Watering Wins
1. Preventing Overwatering (The #1 Killer)
Overwatering causes more houseplant deaths than any other issue. Bottom watering dramatically reduces this risk because plants self-regulate their water intake. Once the soil reaches saturation, capillary action stops—you physically cannot force more water into already-wet soil. Remove the plant after 15-30 minutes, and any excess drains away naturally.
With top watering, nothing stops you from pouring too much water except your own discipline. Many plant parents overwater from above simply because it’s easy to “add just a little more.”
2. Encouraging Deep, Strong Roots
Where water comes from determines where roots grow. Bottom watering encourages roots to grow downward and outward, seeking moisture from below. This creates extensive, robust root systems that anchor plants securely and access nutrients more effectively.
Frequent top watering does the opposite—roots congregate near the moist surface rather than exploring deeper. These shallow root systems make plants less stable, more drought-sensitive, and more vulnerable to stress.
3. Eliminating Fungus Gnats
Those annoying tiny flies hovering around your plants? They’re fungus gnats, and they breed in the moist surface soil created by regular top watering. Their larvae feed on organic matter in the top inch of soil.
Bottom watering keeps the soil surface relatively dry between waterings while maintaining moisture in deeper layers where roots live. This dry surface disrupts the fungus gnat breeding cycle. Many plant parents report complete elimination of gnat problems within 2-3 weeks of switching to bottom watering.
4. Protecting Sensitive Plants
Some plants suffer damage when water touches their foliage:
- African violets develop ugly brown spots on their fuzzy leaves
- Succulents and cacti can rot when stems stay wet
- Begonias get water spots and fungal issues
- Snake plants rot at the crown when water collects there
Bottom watering keeps all foliage completely dry while still hydrating roots—perfect for these finicky species.
5. Preventing Soil Compaction
The force of water poured from above gradually compacts surface soil, especially if you pour too quickly. Over time, this creates a hardened crust that reduces porosity and can even repel water instead of absorbing it.
Bottom watering eliminates this mechanical stress entirely. Water enters gently through microscopic soil pores without disturbing structure.
6. Batch Processing Large Collections
If you have 20+ plants, bottom watering saves time through batch processing. Fill a large tray or your bathtub, place multiple pots in the water simultaneously, set a timer, and walk away. In 20-30 minutes, you’ve watered 10-15 plants with minimal effort.
When Top Watering Wins
1. Speed and Convenience
Top watering takes 1-2 minutes per plant. Pour water, wait for drainage, done. No sitting around for 20 minutes checking if soil is moist yet. For busy people or those with just a few plants, this efficiency is hard to beat.
2. Natural Salt Flushing
Here’s the biggest problem with exclusive bottom watering: mineral salts and fertilizer residue accumulate in the upper soil layers. As water wicks upward and evaporates from the surface, dissolved minerals stay behind. Over time, this creates a white crusty layer that can damage roots and alter soil chemistry.
Top watering flushes these salts downward and out the drainage holes with every watering. This natural cleaning action keeps soil chemistry balanced without extra effort.
3. Works for Any Pot Type
Bottom watering requires specific conditions: drainage holes, appropriate pot size for moving, and saucers to hold water. Top watering works for everything:
- Heavy floor planters too large to move
- Hanging baskets
- Decorative cache pots (though drainage holes are always recommended)
- Plants mounted on boards
- Outdoor containers
4. Practical for Large Plants
Try lifting a 15-gallon fiddle leaf fig or mature monstera to your sink for bottom watering. It’s physically impractical for most people. Top watering with a watering can or hose remains the only realistic option for substantial specimens.
5. Targeted Watering
Sometimes specific areas of a pot dry faster due to root density, sun exposure, or pot positioning. Top watering lets you target those dry zones specifically—something bottom watering’s uniform distribution can’t address.
6. No Special Equipment
Top watering works with any water source: watering cans, cups, bathroom faucets, garden hoses, or even shower heads. Bottom watering requires saucers, trays, or access to a sink/tub large enough to hold your pots.
The Verdict: Context is Everything
After examining both methods thoroughly, here’s the answer to “which is better”: It depends on your specific situation.
Neither approach is universally superior. Bottom watering excels at preventing overwatering and promoting healthy roots but requires more time and causes salt buildup. Top watering offers unmatched convenience and natural salt removal but risks overwatering and encourages shallow roots.
The smartest approach? Combine both methods strategically.
How to Do It Right: Step-by-Step Guides
Technique matters enormously. Here’s exactly how to execute each method for optimal results.
Bottom Watering: 7-Step Process
What you need: Container/tray/sink, room-temperature water, timer
Step 1: Check soil moisture first Insert your finger 2 inches into the soil. Only proceed if it feels dry at this depth. Never water on a fixed schedule—always check first.
Step 2: Prepare the water bath Fill your container with 1-2 inches of room-temperature water. Cold water shocks roots and slows absorption. The water level should reach about one-quarter up your pot’s height.
Step 3: Submerge drainage holes Place the pot in water, ensuring drainage holes are fully submerged but water doesn’t reach the soil surface (that would just be top watering from the side).
Step 4: Set your timer
- Small pots (4-6 inches): 10-15 minutes
- Medium pots (6-10 inches): 15-25 minutes
- Large pots (10+ inches): 25-35 minutes
Step 5: Check if water reached the top After the minimum time, touch the top inch of soil. It should feel damp. If still dry, allow another 5-10 minutes.
Step 6: Remove and drain thoroughly Place the pot on a drainage surface (sink, bathtub, outdoor area) for 5-10 minutes. Gravity will pull excess water out the bottom. Never skip this step.
Step 7: Return to position Place the plant back in its saucer or decorative pot. Check back in 30 minutes and empty any water that’s accumulated in the saucer. Plants should never sit in standing water.
Critical warning: Never leave plants soaking for hours. Extended submersion suffocates roots just like overwatering from above.
Top Watering: 6-Step Process
What you need: Watering can (narrow spout preferred), room-temperature water, saucer
Step 1: Check soil moisture first Same as bottom watering—insert finger 2 inches deep. Water only if dry at this depth.
Step 2: Water slowly and evenly Pour water gently across the entire soil surface, moving in circles. Don’t just water one spot. Water should absorb quickly; if it pools on the surface, you’re pouring too fast. Avoid splashing leaves, especially on fuzzy-leaved plants.
Step 3: Water until drainage This is critical: continue pouring until water flows freely from drainage holes. This is the only way to ensure the entire root ball gets moistened, not just the top layer. For a typical 6-8 inch pot, this usually requires 1-2 cups of water.
Step 4: Let it drain completely Allow the pot to sit in the sink or on a drainage surface for 5-10 minutes. Don’t rush this—you want excess water fully drained before returning it to its saucer.
Step 5: Empty the saucer Return the plant to its saucer, then check back in 15-30 minutes. Pour out any accumulated water. Plants sitting in water for hours develop root rot.
Step 6: Document and observe Note the date in a plant journal or phone app. Observe how many days until the soil feels dry again—this establishes your plant’s individual watering schedule.
Pro tip: If you accidentally get water on sensitive leaves, gently blot with a soft cloth to prevent spotting or fungal issues.
Your Smart Watering Strategy
The most effective approach combines both methods strategically. Here’s your action plan.
The 80/20 Hybrid Approach
Use bottom watering for 75-80% of your watering sessions to enjoy its benefits: overwatering prevention, deep root development, and fungus gnat control.
Top water once monthly (about 20% of sessions) specifically to flush accumulated salts and minerals. When you do this monthly flush, use extra water—pour until water runs clear from drainage holes. This thorough rinsing carries dissolved salts away before they reach problematic levels.
Why this works: You get bottom watering’s advantages (healthy roots, no pests, reduced overwatering) while preventing the salt accumulation that’s its main drawback. It’s the best of both worlds.
Plant-Specific Recommendations
Some plants have strong preferences. Match your method to your plant:
Bottom watering works best for:
- African violets (water spots on leaves)
- Succulents and cacti (hate wet stems)
- Snake plants (prevent crown rot)
- Begonias (avoid foliar damage)
- Cyclamen (protect tuber)
- String of pearls/hearts (trailing stems stay dry)
- Any seedlings or cuttings (gentle moisture)
Top watering works best for:
- Large floor plants (fiddle leaf figs, monstera, bird of paradise)
- Hanging baskets (impractical to take down)
- Plants without drainage holes (though these need careful attention)
- Very fast-draining mixes (orchid bark)
- Ferns (tolerate and enjoy wet fronds)
Either method works fine for:
- Pothos and philodendrons
- Spider plants
- Peace lilies
- ZZ plants
- Most tropical houseplants
Switch methods when problems arise:
- Fungus gnat outbreak? → Switch to bottom watering
- White crust on soil? → Increase top watering frequency
- Suspected root rot? → Try bottom watering to prevent overwatering
- Plant not improving? → Try the opposite method
Seasonal Adjustments
Spring and Summer (active growth): Water more frequently as plants grow vigorously. Bottom watering works excellently to support the rapid root development happening during this period. Check soil moisture every 5-7 days.
Fall and Winter (dormancy): Most houseplants need significantly less water during shorter days. Extend time between waterings—check every 10-14 days instead. Top watering may actually be more practical since plants dry so slowly that batch bottom watering becomes unnecessary.
Universal rule: Never water on a fixed schedule regardless of season. Always check soil moisture before watering. A plant might need water every 7 days in July but only every 18 days in January.
Troubleshooting Common Problems
Even with perfect technique, issues arise. Here’s how to solve them:
Problem: White crusty layer on soil surface Cause: Salt and mineral accumulation from bottom watering (or hard tap water) Solution: Top water thoroughly to flush salts through drainage holes. Do this monthly if bottom watering regularly. You can also scrape away the crust and top-dress with fresh soil.
Problem: Fungus gnats everywhere Cause: Constantly moist surface soil from frequent top watering Solution: Switch to bottom watering immediately to keep the surface dry. Let the top inch dry completely between waterings. Add yellow sticky traps to catch adults. The population will decline within 2-3 weeks.
Problem: Plant wilting despite regular watering Cause: Either overwatering (roots rotted, can’t absorb water) or severe underwatering Solution: Check soil moisture. If wet and wilting = overwatering causing root rot. If bone dry and wilting = increase watering frequency. Remove plant from pot to inspect roots—healthy roots are white/tan and firm, rotted roots are brown/black and mushy.
Problem: Water not absorbing when bottom watering Cause: Soil has become hydrophobic (repels water) from drying completely, or soil is too compacted Solution: Add one drop of dish soap to the water to break surface tension. Alternatively, top water lightly first to start the wicking process, then bottom water. If this keeps happening, repot in fresh, well-draining soil.
Problem: Water running straight through pot without absorbing (top watering) Cause: Severely dried out soil has pulled away from pot edges, creating a gap; or plant is extremely root-bound Solution: Water in multiple small doses, waiting between each pour for absorption. Bottom watering actually works better for this problem. Long-term solution: repot in a larger container with fresh soil.
Problem: Yellow leaves appearing Cause: Most commonly overwatering, but can also be underwatering, natural aging, or nutrient deficiency Solution: Check soil moisture and watering frequency. If soil is consistently wet = reduce watering. If bone dry = increase frequency. If only lower older leaves yellow while new growth looks healthy = natural aging (normal). If widespread yellowing = check roots for rot.
Conclusion: Your Watering Game Plan
Bottom watering versus top watering isn’t about finding a universal winner—it’s about understanding when each method serves your plants best.
Bottom watering excels when you need overwatering protection, want to encourage deep roots, or fight fungus gnats. It’s perfect for African violets, succulents, and small to medium plants you can easily move.
Top watering wins for convenience, large plants, hanging baskets, and its natural ability to flush salts. It’s the practical choice when you need quick results or can’t physically move your pots.
The smartest strategy? Combine both methods. Bottom water for your regular 75-80% of sessions, then top water monthly to flush accumulated salts. This hybrid approach delivers healthy roots, prevents pests, and maintains clean soil chemistry.
Pay attention to your specific plants. Some have strong preferences—honor them. African violets will always prefer bottom watering. Your fiddle leaf fig will always need top watering. And your pothos? It’ll thrive with either method, so choose whatever fits your lifestyle.
Start experimenting with both techniques. Document what works for each plant in your collection. Within a month or two, you’ll develop an intuitive sense of which method each plant prefers. Your plants will tell you through their growth, root development, and overall health.
The goal isn’t perfection—it’s consistent, thoughtful care that responds to your plants‘ actual needs rather than following rigid rules. Master both methods, stay flexible, and let your plants guide you.
