To use the peels, they need to be grated or crushed into tiny pieces then they can be added to the soil as an amendment. They will release nutrients into the soil when they break down and can help improve the soil’s structure. For new plants, add them into the soil by mixing them into the bottom of planting holes. For established plants, spread them on the surface of the soil around their base and work them in using a rake or fork.
To use the juice, dilute two tablespoons in a liter of water and add to the soil a few times a week. Avoid watering the leaves as it can cause damage. After a few weeks, retest the pH of your soil to see if it is more acidic or if you need to keep going. Always use this gardening hack in moderation and monitor the effects so you can make any necessary adjustments to the amount of lemon juice or peels you use.