“Can I mix different potting soils? I plan to repot a couple of spider plants (Chlorophytum comosum) to larger containers. They are doing good and are currently in Black Gold Natural & Organic Potting Soil. I have some of this potting soil left in the bag, but it’s not going to be enough. Should I buy more of the same or should I mix it with one of your other products?” Thank you. Question from Crea of Farmington, Missouri
Answer: Different potting soils do have different qualities, but it will not negatively impact your spider plant to combine different mixes that it will ultimately grow well in. Spider plants are adaptable and forgiving. Just be sure that the new mix you choose holds water well but also drains well. Check out all of our general potting mixes by clicking on this link. Each is described in detail with respect to its ingredients and qualities. If your spider plant is root bound, I recommend you click here to read a good article about what to do in this situation.
“If you plant flowers in a flowerpot, do you ever have to change out the soil, or does the soil never lose its nutrients? Question from Jessica of Phoenix City, Alabama
Answer: Potting soil must be changed or replenished every couple of years or so for many reasons beyond the fact that a plant may have outgrown its pot. Not only do plants remove fertilizer nutrients in the soil, but the soil components also break down and become more acidic over time. You can always add fresh fertilizer to the potting mix, but the changes caused by decomposition can only be fixed by adding fresh potting soil. Here are four important characteristics of fresh soil that are lost with age.
The Four Important Characteristics of Fresh Potting Soil
Lots of air pockets to facilitate good drainage and aeration for healthy root growth. (As potting soil ages, and its organic matter breaks down, these air pockets are lost.)
Better water-holding characteristics. (As potting soil ages, water is less available to plant roots.)
A more neutral pH. (As potting soil ages, it becomes more acidic, which many plants do not like.)
A better ability to distribute nutrients to plants. (As potting soil ages, plant roots have a harder time accessing fertilizer in the soil.)
After two to three years, replenish your pots with fresh potting soil. When I add new potting soil to my containers, I take the old mix and add it to my garden beds as an amendment. That way, nothing is wasted.
“How do I know when to get a bigger pot for my jade plant?” Question from Grady of Akron, Ohio
Answer: There are two ways to tell if your jade plant (Crassula ovata) has outgrown its pot:
The plant has become top-heavy
The roots have densely grown to the pot walls
You can tell if the roots have densely grown to the pot walls by feeling down into the soil. You will be able to feel the roots. Another test is to gently lift the plant from the pot to see if the root mass stays together. If it does, it’s time to repot.
The best time to repot a jade is in spring before the plant starts to actively grow. Choose a pot that is an inch or two larger than the previous one. Gently loosen the root ball and replant your jade in Black Gold Cactus Mix, which is custom-made for succulents. This is also a good time to blend in a slow-release fertilizer formulated for succulents. Fill in around the base and edges with the new mix, and water until the bottom saucer is filled. Then keep the soil lightly moist, allowing the plant to dry between watering.