Why you should use plant food for your tomatoes - and the ways to do it

Tomatoes grow fast and are therefore in great need of nutrition. A seed has enough nutrients  to grow on its own, and there are nutrients in the soil. But if you want a big harvest of tomatoes, you should consider adding plant food. Plant food can either be purchased or made your own.

When should I add plant food to my tomato plants?

Tomatoes need nutrition to grow and develop properly. If you want strong and healthy plants, you need to make sure they have enough nutrition during the whole season. 

When you replant your tomato plants, the new soil is full of nutrition. But about three weeks after being replanted, they have used up most of the nutrition in the soil. By then, it is time to add more nutrition, either by adding liquid plant food, plant food spikes, or your own homemade plant food.

What type of plant food should I choose?

Depending on if you are cultivating indoors or outdoors, and depending on your cultivation scale, there are different alternatives of plant food to choose between. 

If you have a smaller cultivation, or to make it easier on yourself, purchasing plant food is preferable. There is plant food made especially for tomatoes. Another alternative for potted plants is plant food spikes, which are small sticks that add nutrients to the soil. 

Plants automatically regulate how much of each ingredient they absorb from the nutrition they are provided with. Therefore, you can use similar nutrition for most plants. 

If you have a larger cultivation you might want to try making your own homemade plant food. One way of doing this is by adding compost to the soil you are cultivating with. If you have a bokashi compost at home, that is another alternative. Bokashi composting can shortly be described as fermented kitchen waste that creates a liquid called leachate (sometimes called Bokashi tea or juice). By diluting leachate with water, you can water your plants with it.

How much plant food should I add?

Adding the right amount of plant food to your plants might seem tricky in the beginning. Always read the instructions of the product for the right dosage if you purchase your plant food. Generally, if choosing liquid plant food, the best way is to add small doses often, at least once a week, depending on the type of plant food you choose. Remember to dilute properly if you use nettle water as plant food, or if you use leachate from bokashi composting. When diluting, one part leachate or nettle water per 100 or 200 parts of water is usually enough. Use your diluted water whenever you hydrate your plants. 

If you cultivate in pots, you could also use plant food spikes. Push the spikes into the soil around the edges of the pot. Whenever you water your plants, the spikes will release the right amount of nutrients into the soil. The spikes can stay in the pot for up to three months before it is time to replace them with new ones.

How long should I keep adding plant food?

Plant’s nutritional needs differ depending on where they are in their growth process. Once they are developing their fruits, they need less nitrogen (which is good for the growth of the leaves) and are in more need of phosphorus and potassium (which is good for fruiting). These nutrients can be found in most of our liquid plant foods. 

Tomato plants need nutrition during the entire season in order to develop fruit until the end of summer. If cultivating outdoors, the tomatoes will wither once  fall comes, and then die when the first frost hits. After replanting and until fall, add plant food about 1-2 weeks apart, or according to the instructions of the plant food you purchased.