Container plants need the right soil
Q: My containers and baskets are wilting faster than I can water them most days. Are there any tips for better watering? Less time consuming? Adding to soil? Anything that will help!
— Darlene from Poland
A: You are not the only one asking these questions and experiencing lots of challenges with keeping plants hydrated and healthy. These two things are intertwined. Just like humans, happy, healthy plants are less prone to disease issues.
Nearly 100 percent of our containers and baskets are filled with potting mix. If you lift a bag of potting soil, then lift a bag of potting mix — you will notice a big difference. The potting soil is much heavier. That’s just one of the many differences between these two products.
Potting mixes don’t really include any soil at all. Ingredients include peat moss, vermiculite and other materials. These soilless mixes provide better drainage and better conditions for root growth. They are lightweight so we can move containers and baskets with ease.
The mineral content of soil is what helps retain nutrients and increase water holding capacity. This means that we must water and fertilize plants grown in potting mixes for optimum performance.
For fertilizer, most purchased plants and baskets have some type of slow release fertilize that can last for a long time. You can purchase mixes that retain more moisture. These are helpful, but still need monitored for moisture levels.
To learn more about potting mix and potting soil, go to http://go.osu.edu/soilvsmix
Now that we know more about what our plants are growing in, we can understand the watering and fertilizer requirements and what to look for to help the plant get what it needs. As Darlene has noticed, it is not always easy.
This time of year, you will probably need to water every day — sometimes, twice a day for larger plants in smaller baskets. Anytime you see wilting, it may be time to water. Moving some containers to avoid some of the hottest sun of the day is a possibility on the hottest days to reduce the need to water and the heat stress on plants.
The biggest problem with watering is not testing the soil with your finger before you water. This is the only way to know when and how to water. If the soil is dry, you water. If it is wet, you hold off watering. Simple? Not really.
What if the soil is really, really dry? This is when we tend to not water properly. If watering was missed and a plant is wilting, the soil / mix is so dry that the water flows over and around the soil / mix and does not get absorbed. In this case, you need to water, come back in a half hour and water again. Keep repating this until the soil becomes wet. Baskets and smaller containers can be placed in larger containers of water to allow the soil to re-hydrate properly.
Fertilization may also be a challenge. Temperature, water and other factors affect the release rate of the slow-release fertilizers that were in the potting mix of the basket you purchased this spring. With all the extra heat and watering this season, you will most likely need to start using a water-soluble fertilizer product. Watch for changes in leaf color, fewer flowers and other signs the plants need a pick-me-up. Be sure to read and follow all label directions for fertilizers.
To learn more about watering and rehydrating your containers and baskets, go to http://go.osu .edu/hydratesoil.
Eric Barrett is OSU Extension educator for Agriculture and Natural Resources in Mahoning County. Submit your questions to our office at 330-533-5538. Regular clinic hours are 10 a.m. to noon Thursdays or visit go.osu.edu/virtualclinic.