Food will be so bland without herbs and spices. Spices are so important during the olden days that the economy of the world was driven by spices which is known as the Spice Trade. In fact during the olden days people went to war over spices which is known as the Spice Wars.
The normal way to earn money with herbs and spices is to grow them either or both in your farm or garden and then sell them. There are restaurateurs who grow them right in their own restaurants and then serve them to their clients who usually pay a premium for them because they know that the food being served to them comes from a distinct restaurant only.
One distinct advantage of herbs and spices are their small size as compared to fruits and vegetables which is advantageous for packing and delivery cost concerns. That is why there are a lot of enterprising people who buy them wholesale and then repack them in smaller sizes like very small sachets and sell them at a higher profit margin.
In the Philippines for example we used to sell black pepper in gram sachets because our customers think buying grocery store packed black peppers are still too big and not practical because they spoil first before being completely used. There are also a lot of people who hardly use herbs and spices because of personal taste.
Herbs and spices can be so identified with certain dishes that entire lines of seasoning powder mixes are now being marketed especially for them. Each country would have their own lines based on their local dishes. This is one home based business one can profitably enter especially if one has a strong social media following related to cooking.
One of the best instant powdered mix or sauce to market for is for spaghetti. Spaghetti is so widely known that almost all countries in the world have custom powdered mixes and sauces of their own. One can specialise and achieve economies of scale by first specialising on it.
For example in the Philippines instant spaghetti sauce usually comes in a sweet tangy taste which is common for most brands. There is no discernible difference from one brand to another. In Australia however there are varying types of spaghetti sauce according to a particular spaghetti dish. I eat more Spaghetti in Australia than in the Philippines as a result.
Due to their small sizes one can relatively grow a large number of plant herbs and spices in small spaces of land. Culinary herbs are ideal for small-scale growing because of their specialised growing conditions and labor intensive needs. This puts their price at a premium as compared to other food plants.
You can grow herbs at home. You can grow them in your garden, backyard, windowsills and any place in your house that is convenient for you to have soil and can accommodate water spillage. Your herbs must have access to sunshine as herbs just like any other plants need a healthy dose of exposure to the sun to grow.
Do not despair however if your place does not have the previously mentioned home features. Most herbs can still be grown indoors even in tight spaces. You just need herb container assemblies that would not spill water and hence not spoil your furnitures, carpets or wooden floors if they drip in them. Herb access to sunlight is also possible if you strategically place them in areas inside your homes where sunlight shines through.
You can also grow herbs in your basement. Just like growing your herbs inside your house where there are water spillage risks and herb access to sunshine can be logistically hard basement growing can eliminate this problems. One can setup a non-spilling irrigation system and substitute sunshine with lights powered by electricity.
Though proof of the commercial viability of growing herbs is hard to come by online I managed to find an article dated 2018 from Spore titled Kenyan farmers profit from growing aromatic market. The article reported how an African farmer doubled his income when he switched to growing herbs.
One interesting spice you should look into is Saffron. Saffron is primarily grown in a few countries only like Greece, India, Iran and Morocco and is the most expensive spice in the world. This is due to the high cost of growing it and also because of its distinctive flavour, smell and appearance. There are however people who are able to grow them in their homes.
Herbs and Spices are ideal for people with limited planting space. Basil and Mint for example will root even if they are just placed in a glass. For their small sizes they outperform bigger fruits and vegetables in terms of selling price by volume which is their greatest advantage to sellers with limited planting resources.