How to Make and Use Potato Tea for Your Garden

Potato tea is a liquid plant fertilizer created by utilizing the water from boiled potatoes or by steeping potato peels in water. This method repurposes kitchen scraps into a nutrient source for garden plants. By extracting compounds from the potatoes, this liquid can be applied to soil to support plant growth and provide a no-cost, supplemental feeding.

Benefits of Potato Tea for Plants

The primary benefit of using potato tea is the nutritional content it provides. Potatoes are a source of potassium, a macronutrient that regulates a plant’s metabolic processes, strengthens cell walls for sturdier stems, and improves resilience against environmental stressors. It also contributes to the development of flowers and fruits.

Beyond potassium, the water contains starches released from the potatoes during boiling. These starches act as a food source for beneficial microorganisms in the soil. A healthy microbial population improves soil structure and helps break down organic matter, making nutrients more accessible to plant roots. The tea also contains smaller amounts of other minerals, such as magnesium and calcium, which support functions like chlorophyll production.

How to Make Potato Tea

Creating potato tea is a straightforward process. You will need potato peels or leftover pieces from a handful of potatoes, water, a pot for boiling, a strainer, and a container. The most common method involves using the water left after boiling potatoes, as it is already infused with nutrients. It is important to avoid using water that has been salted, as salt is detrimental to plant health by inhibiting water absorption.

To make the tea, boil the potatoes or peels in a pot of water for approximately 15-20 minutes, allowing the nutrients to leach into the liquid. Once finished, allow the water to cool completely to room temperature, as applying hot liquid can shock plant roots and cause damage. After it has cooled, strain the liquid through a fine-mesh sieve or cheesecloth to remove all solid potato pieces.

For an alternative no-boil method, you can place potato peels in a jar, cover them with water, and let them steep for several days. This fermentation process also extracts nutrients, though it takes longer. The goal is to create a nutrient-rich liquid that can be easily absorbed by your plants.

Applying Potato Tea to Your Garden

Once your potato tea has cooled and been strained, it is ready for application. The most direct way to use it is as a soil drench, pouring it directly onto the soil at the base of your plants. This delivers the nutrients straight to the root zone where they can be readily absorbed. Aim to water the plants with the tea when the soil is already slightly moist to improve absorption.

The frequency of application depends on the needs of your plants, but a guideline is to use the tea once every two to four weeks during the active growing season. Plants that are heavy feeders respond particularly well to the additional potassium. These plants require more nutrients to support their growth and include:

• Tomatoes
• Peppers
• Roses
• Various root vegetables

It is best to apply the tea in the early morning or late evening. Applying it during the hottest part of the day can lead to faster evaporation and may reduce its effectiveness. Observe how your plants respond after an application and adjust the frequency as needed based on their appearance and growth.

Potential Considerations and Risks

While potato tea is beneficial, there are a few considerations. The liquid, especially if stored, can begin to ferment and develop a sour odor or grow mold. To avoid this, it is best to use the tea fresh within a day or two of making it. If you need to store it, keep it in an airtight container in the refrigerator for no more than a few days.

The starchy nature of the tea can sometimes attract pests, particularly fungus gnats, if the soil becomes overly saturated and is not allowed to dry properly. To mitigate this risk, ensure the soil dries out between waterings. This prevents the consistently damp conditions that are favorable for pest breeding.