Growing cactus from seeds can be a rewarding and fun experience, but it can also be challenging, especially for beginners. Here are some tips to help you get started:
Based on the description you provided, there are several possible reasons for the brown and dry leaves on your basil It's generally not recommended to use sand from a DIY store for gardening purposes as it may contain harmful chemicals or contaminants. Horticultural sharp sand, on the other hand, is specifically designed for gardening and is free of contaminants. Using horticultural sharp sand can help improve soil drainage and aeration, which is beneficial for root development in carrots and onions.
However, keep in mind that sharp sand alone is not a suitable growing medium for plants as it lacks nutrients. It's best to mix the sharp sand with your existing soil/compost/perlite mix to improve its texture and drainage. A ratio of 1 part sharp sand to 3-4 parts soil/compost mix is a good starting point.
If you're concerned about the cost of horticultural sharp sand, you may want to consider alternatives such as perlite or vermiculite, which can also help improve soil drainage and aeration. These materials are typically more affordable and easier to find than horticultural sharp sand.