Nutrients



In order to grow, plants need water, nitrogen, phosphorus, potassium, and numerous micronutrients. Most of these nutrients are provided through the soil, although some come from the air.

You must research the specific needs of your plant, because some uncommon micronutrients are required for some species. Things like magnesium, sulfur, and iron may be important to your plant. A general fertilizer will not work for every plant you have. You should test your soil periodically and adjust the amount of nutrients to fit what they are supposed to be.

If you plant does not need potassium, you can use blood meal instead. You should add about a teaspoon per square foot. Slow growing plants like herbs need less fertilizer - sometimes very little.

Fertilizer should be added fully in the spring, with small additions made in the summer. This can vary from plant to plant, so it's important that you check the specific needs of your plants.

Water

The species of plant you have will also dictate what it's watering schedule should be. The type of soil is important in determining this as well. For example, a clay-like soil will retain water, so it does not need watered as often as sandy soil.

You can test the soil of your indoor house plants with your finger. If you feel that the soil is moist, but not soaked, it is good. You can test deeper with a tongue depressor. If the wood becomes wet it shows that the soil is still moist. The third way to test is with the professional instrument, a hygrometer.

If the soil is not moist at all, you can water it and retest it to see if it is fixed. If it is hard to consistently get the right amount, adding some gypsum will help dry out the areas that are too moist. You must consider how much soil there is when deciding how much water to add.

You must be careful not to put a small plant in too large of a pot because the soil can retain too much soil. The plant could then get a disease or root rot. Just like the amount of fertilizer and water is determined by the size and type of plant you have, you should base the amount of soil you use on that as well.