Is there anything that can be added to the soil which will make fruit sweeter?

Yes, there are a few things that can be added to the soil to make fruit sweeter. These include:

- Potassium: Potassium is an essential nutrient for plants, and it helps to regulate the water balance in the fruit. Adding potassium to the soil can help to increase the sweetness of the fruit. This can be done by using a potassium-rich fertilizer, such as wood ashes or potassium sulfate.

- Phosphorus: Phosphorus is another important nutrient for plants, and it helps to promote the growth of the fruit. Adding phosphorus to the soil can help to increase the sweetness of the fruit. This can be done by using a phosphorus-rich fertilizer, such as bone meal or superphosphate.

- Magnesium: Magnesium is a mineral that is essential for the production of chlorophyll, which is the green pigment in plants. Adding magnesium to the soil can help to increase the sweetness of the fruit by promoting the growth of the plant and the production of chlorophyll. This can be done by using a magnesium-rich fertilizer, such as Epsom salt or dolomitic lime.

It is important to note that adding too much of any of these nutrients to the soil can be harmful to the plant, so it is important to follow the directions on the fertilizer package carefully.