Don’t Let Your Office Plants Die – Prevent Hydrophobic Soil

Written by, Katie Maiers, A&D Market Manager and Business Development at COE

The Frustration of Dying Office Plants

Having lush, green office plants can make your workspace more inviting and improve air quality. But it’s incredibly frustrating when your plants keep wilting and dying despite your diligent efforts to water them. You think you’re doing everything right – checking the soil, adding water when it feels dry. Yet your poor plants don’t seem to be absorbing any of that precious moisture.

The likely culprit? Hydrophobic soil.

What is Hydrophobic Soil?

Signs Your Soil Has Become Hydrophobic

Hydrophobic means the soil has become water repellent or water-resistant. When you try to water plants with hydrophobic soil, the water simply beads up and runs off the dry, compacted soil instead of being absorbed into the root zone where the plants need it most.

You’ll know your soil has become hydrophobic if:

  • Water pours out from the sides and bottom of the pot instead of soaking in
  • The top couple inches of soil appear bone dry even after watering
  • Your plant appears wilted or dried out despite your watering efforts

This issue tends to develop over time as the potting mix breaks down and becomes hydrophobic. Constant wetness followed by periods of complete dryness causes the natural and organic materials in the potting mix to decompose at different rates, leading to compaction.

The Science Behind Hydrophobic Soil

On a scientific level, hydrophobic soils develop waxy coatings from the release of hydrophobic compounds during microbial decomposition of organic matter like peat moss. As the potting mix dries out between waterings, the waxy coatings repel moisture rather than absorbing it.

The formation of hydrophobic soils also depends on the soil type and texture. Sandy soils are more prone to becoming hydrophobic, while clay soils are less affected since the clay particles help bind moisture.

Preventative Measures for Hydrophobic Soil

The best solution is to take preventative measures from the start to keep your potting mix in good condition. This helps ensure your plants get the moisture they need.

1. Check Soil Moisture Weekly

Go around once a week and check each of your office plants. Stick your finger an inch down into the potting mix – if it feels dry, it’s time to water. If it still has some moisture, skip watering that plant until the next week.

Checking soil moisture regularly helps prevent both underwatering and overwatering, the two main culprits of hydrophobic soil development.

2. Water From the Bottom for Succulents & Cacti

Succulents like jade, echeveria, and cacti are especially prone to developing hydrophobic soil since they require infrequent watering and dry potting mixes.

For these plants, water them by letting the entire pot sit in a tub or tray of water for 20-30 minutes. This allows the dry soil to slowly soak up moisture from the bottom up into the root zone. Then discard any excess water in the tray.

Bottom watering succulents avoids compacting the potting mix and allows for more even absorption throughout the pot. Just be sure not to leave the plant sitting in any drained water.

3. Repot Annually With Fresh Potting Mix

No matter how well you care for your plant’s soil, the potting mix will inevitably break down over time. It’s recommended to repot your plants annually with a fresh, moisture-retaining potting mix that contains organic materials like peat moss, compost, or bark.

The organic matter helps retain moisture while also providing vital nutrients as it breaks down. It also improves aeration and drainage in the pot.

When repotting, gently knock away as much of the old compacted soil as possible from the plant’s rootball before setting it into the new, fluffy potting mix.

Dealing With Hydrophobic Soil

Despite your best preventative efforts, hydrophobic soil can still develop over time. When it does, you have a few options:

Use a Wetting Agent

One of the easiest ways to temporarily restore a hydrophobic soil’s ability to absorb moisture is to use a wetting agent or soil surfactant. These work by reducing the surface tension of water droplets so they can penetrate into the potting mix more easily.

You can purchase commercial wetting agents, or make your own inexpensive version by adding a couple drops of liquid dish soap or washing soda to your watering can before watering. The soap helps break the surface tension so the water can soak in instead of beading up.

Wetting agents are a quick fix, but don’t permanently resolve hydrophobic soil issues. You’ll need to reapply with each watering until you can repot with fresh mix.

Try the Slice and Soak Method

If the hydrophobic soil is really compacted, you may need to take more extreme measures to rehydrate it. One method is to take a clean knife, scissors or trowel and make some vertical slices or holes down into the potting mix.

Then, place the entire pot in a tub or tray of water just deep enough to reach the sliced sections. Allow it to soak for 30 minutes to an hour until the water absorbs through the holes and rehydrates the rootball.

Drain off any excess water still sitting in the tray before putting the plant back in its usual spot. You may need to repeat this slice and soak method a couple of times until the soil is evenly rehydrated.

Repot With New Soil Mixture

If all else fails, you may simply need to bite the bullet and repot the plant with a fresh potting mix blend. This gives you a clean slate to work with and resets the soil to prevent hydrophobic tendencies.

When repotting due to hydrophobic soil, it’s best to use a potting mix formulated for moisture control that contains ingredients like coconut coir to aid absorption. Add an extra handful of horticultural sand or perlite as well to improve drainage and aeration.

Keep Your Office Plants Thriving

With some simple preventative care and close monitoring, you can avoid the pitfalls of hydrophobic soil. Pay attention to each plant’s individual soil condition and adjust your watering schedule as needed depending on the type of plant, pot size, and environmental factors like light and airflow.

Don’t let hydrophobic soil leave your office oasis wilting and dry. Follow these tips and your lush, thriving plants are sure to brighten up your workspace!