How Often To Water Lemongrass

Getting the watering right is the single most important thing you can do for a healthy lemongrass plant. If you’re wondering how often to water lemongrass, the simple answer is: it depends. This guide will cut through the confusion and give you the clear, practical advice you need to water your lemongrass perfectly, whether it’s in a pot or in your garden soil.

There is no universal schedule, like “every Tuesday.” Your lemongrass watering frequency is dictated by its environment. The goal is to mimic its natural tropical habitat—periods of generous moisture followed by a slight drying out. Overwatering is a far more common killer than underwatering for this robust grass.

The Core Watering Principle: The Knuckle Test

Forget the calendar. Your finger is your best tool. This method works for both container and in-ground plants.

Insert your index finger into the soil near the base of the plant.
Push it down to about your second knuckle (roughly 2 inches deep).
Feel the soil at your fingertip. Is it dry, damp, or wet?

If it feels dry: It’s time to water thoroughly.
If it feels damp or cool: Hold off and check again in a day or two.
If it feels wet: You are overwatering. Let it dry out significantly.

Watering Potted Lemongrass

Potted plants dry out faster and need more frequent attention. In general, during the hot, active growing season (spring and summer), you might water every 2 to 4 days. But always use the knuckle test to confirm.

Pot Choice is Key: Always use a pot with excellent drainage holes. A pot that’s too large holds wet soil for too long, risking root rot.
Watering Technique: Water slowly at the base of the plant until you see water running freely out the drainage holes. This ensures the entire root ball gets moisture.
Seasonal Changes: In fall and winter, growth slows. Water much less frequently, sometimes only every 2-3 weeks, always checking the soil first.

Watering In-Ground Lemongrass

Garden-planted lemongrass is more forgiving and drought-tolerant once established. It can access deeper soil moisture.

Establishment Phase (First Season): Water deeply 1-2 times per week to encourage deep root growth. Use the knuckle test to avoid overdoing it.
Established Plants: Often, natural rainfall is enough. During dry spells or heatwaves, provide a deep soaking weekly. The goal is long, deep drinks that encourage resilience.
Mulch Magic: Apply a 2-3 inch layer of organic mulch (like straw or wood chips) around the base. This retains soil moisture, keeps roots cooler, and suppresses weeds.

Signs You’re Underwatering Lemongrass

Lemongrass is tough, but it will tell you when it’s thirsty.

Leaf tips turn brown and crispy, starting at the very ends.
The entire leaf blade may roll or curl inward.
Growth becomes stunted or stops completely.
The plant looks generally dry and pale.

Signs You’re Overwatering Lemongrass

This is more dangerous and must be corrected quickly.

Lower leaves turn yellow, often starting from the bottom of the plant up.
The stalks or base of the plant may feel soft, mushy, or smell unpleasant.
Visible mold or algae on the soil surface.
A general droopiness despite wet soil (a sign of root rot).

5 Key Factors That Change Watering Frequency

Your neighbor’s watering schedule will differ from yours. Here’s why:

Climate & Weather: Hot, dry, windy conditions dry soil fast. Cool, cloudy, humid weather means less frequent watering.
Season: Water heavily in spring/summer (growth phase). Reduce dramatically in fall/winter (dormancy).
Soil Type: Sandy soil drains quickly and needs more frequent water. Clay soil holds moisture longer and needs less.
Plant Size & Pot Size: A large, root-bound plant in a small pot dries out faster than a small plant in a generously sized container.
Sun Exposure: A plant in full, all-day sun needs more water than one in partial afternoon shade.

Step-by-Step: How to Water Lemongrass Correctly

Check the Soil: Perform the knuckle test. Only proceed if the top 2 inches are dry.
Choose the Time: Water in the early morning. This allows leaves to dry in the sun, preventing fungal disease, and reduces water loss to evaporation.
Water the Base: Aim your hose or watering can at the soil around the base of the plant. Avoid wetting the foliage as much as possible.
Water Deeply: Apply water slowly until it is fully absorbed and, for pots, until it runs freely from the drainage holes. For in-ground plants, ensure the water penetrates at least 6 inches deep.
Let it Drain: Never let a potted plant sit in a saucer full of water. Empty the saucer after 30 minutes.
Monitor and Adjust: Note how long it takes for the soil to dry out. This becomes your personalized guide for next time.

FAQ: Your Lemongrass Watering Questions Answered

Can lemongrass be overwatered?

Absolutely. Overwatering is the most common mistake. It suffocates the roots, leading to root rot, which can quickly kill the plant. Always err on the side of too dry rather than too wet.

How much water does lemongrass need?

It needs a deep watering, not a frequent sprinkle. The quantity isn’t as important as the depth of penetration. Water should reach the entire root zone. For pots, this means watering until it flows from the bottom.

Is lemongrass drought tolerant?

Yes, once its roots are well-established (usually after one growing season), lemongrass has good drought tolerance. It may not grow as vigorously without water, but it will survive dry periods better than many herbs. New plants, however, need consistent moisture.

Should I mist my lemongrass?

No, misting is not necessary and can promote leaf fungal issues. Lemongrass prefers humidity around its roots in the soil, not on its leaves. Focus your watering at the soil level.

How do I know if my lemongrass has root rot?

Signs include yellowing leaves, a foul smell from the soil, and black, mushy roots. If you suspect it, you may need to unpot the plant, trim away any rotten roots, and repot in fresh, well-draining soil. Sometimes its easier to just propogate a healthy stalk from the plant.

Does rainfall count as watering?

Yes, but you should still check. A light shower may only wet the surface. Use your knuckle test after rain to see if the deeper soil got moist. Adjust your next watering accordingly.

Mastering how often to water lemongrass is about observation and adaptation. Start with the knuckle test as your golden rule, pay attention to the signals your plant gives you, and consider the five key factors in your environment. With this approach, you’ll develop a natural rhythm that keeps your lemongrass thriving, ensuring you have a plentiful supply of its fresh, citrusy stalks for your kitchen.