1 quart of rock dust a great thing to have on hand for all your plants both indoor and outdoor.
 
The Soil Bar rock dust is a natural mineral supplement that can be used to improve the health and growth of houseplants. It is made from volcanic ash that is rich in trace minerals, including calcium, magnesium, potassium, and iron.
The Soil Bar rock dust can be beneficial to houseplants in a number of ways:
Improves nutrient uptake: rock dust can help plants to better absorb nutrients from the soil. This can lead to improved growth, flowering, and fruiting.
Increases resistance to pests and diseases: help to strengthen plant cell walls and improve their resistance to pests and diseases.
Improves soil health:  improve soil drainage and aeration. It can also help to increase the water-holding capacity of the soil.
Reduces stress: caused by environmental factors such as drought, heat, and cold.
To use The Soil Bar  rock dust for houseplants, simply mix it into the potting soil before planting. You can also top dress your plants with rock dust every few months.
Here are some specific tips for using rock dust for houseplants:
Mix 1/2 teaspoon of rock dust per inch of pot diameter into the potting soil before planting.
Top dress your plants with 1/4 teaspoon of rock dust per inch of pot diameter every 3-4 months.
Water your plants thoroughly after applying rock dust to help the minerals absorb into the soil.
The Soil Bar rock dust is a safe and effective way to improve the health and growth of your houseplants. It is an affordable and natural way to give your plants the nutrients they need to thrive.
It's totally natural and OMRI listed organic product.  Unlike other fertilizers rock dust will NEVER burn or hurt your plant (no amount is too much in other words) 
 
With such a small application this quart of rock dust will last you for years.  Keep it stored in it's resealable container to maintain freshness.  Stays good for 5 years.