which igneous rock is mixed with soil and used for starting vegetable seeds

That didn't answer the Question.

Igneous rocks like basalt and granite have the highest mineral content, with basalt providing a greater balance of nutrients for optimal plant health and vitality. Created through the cooling and solidification of magma and lava, basalt is the rock material that makes up most of the soils around the world.

I would try basalt or granite.

The igneous rock that is commonly mixed with soil for starting vegetable seeds is called perlite. Perlite is a type of volcanic glass that is formed when obsidian—a natural glass-like igneous rock—comes into contact with water. It is a lightweight and porous material, making it ideal for improving soil drainage and aeration during seed germination.

To use perlite for starting vegetable seeds, you can follow these steps:

1. Prepare your potting mix: Begin by mixing perlite with potting soil, typically in a ratio of 1:1 or 1:2 (perlite to soil). This will depend on the specific needs of your seeds and the type of vegetables you are growing.

2. Sterilize the mixture (optional): If you want to ensure a clean and disease-free environment for your seeds, you can sterilize the perlite and soil mixture before sowing the seeds. This can be done by baking the mixture in an oven at 180-200°C (350-400°F) for about 30 minutes. Allow it to cool before proceeding.

3. Fill your seed trays or pots: Fill the seed trays or pots with the perlite and soil mixture. Make sure to leave some space at the top for watering.

4. Sow the seeds: Follow the instructions for sowing the specific vegetable seeds you are working with. Typically, you will create small indentations in the soil mixture and place the seeds according to the recommended spacing.

5. Water carefully: Perlite helps with drainage while still retaining some moisture. Water your seeds gently to avoid disturbing them and ensure they receive the required moisture for germination.

6. Provide appropriate light and temperature: Place the seed trays/pots in a suitable location with adequate sunlight or artificial light as per the requirements of the vegetable seeds. Also, maintain the recommended temperature range for optimal seed germination.

Remember that different types of vegetables may have specific needs, so be sure to adjust the mixture ratio, watering, and lighting conditions accordingly.

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