Gardening Help Search

Plant Samples

Due to the threat of Boxwood Blight, Rose Rosette and other serious pest/disease issues, the Garden is no longer allowing plant samples to be brought in for identification or diagnosis. These problems can spread to the garden displays and severely impact our living plant collection.

Please help us protect our plants by taking clear photos of the plant you need identified or diagnosed. Images can be emailed to plantinformation@mobot.org or brought to the Plant Doctors at the Center for Home Gardening (Open every day, 9 am - 5 pm).  

For any additional questions regarding samples, please call: 314-577-9562.

Winter Houseplant Care

During the winter the Plant Doctor Desk receives many questions from visitors regarding how to care for their houseplants. Here are some tips for keeping your plants healthy during the long winter months:  
 
Watering: Houseplants grow more slowly in winter and generally need less water since the temperature is cooler and the quality of light is lower. A good way of determining if your plants need water is to stick your fingers into in the soil about an inch. If the soil is moist, hold off on watering. If the soil is dry, your plant needs water. Water the plant until it drains out of the bottom of the pot to ensure the soil is uniformly moist. Discard any extra water in the saucer after the pot has drained. The frequency of watering will depend on your plants, the pot size, temperature, humidity, etc.  
 
Light: Plants not receiving enough light will become etiolated or turn pale in color and will stretch for light. These plants may benefit by being moved to a south or west window, or have light supplemented by grow lights.  
 
Temperature: Keep plants away from hot air blowing from a furnace vent, which can increase evaporation (water loss from soil) and transpiration (water loss from leaf surfaces) and cause the plant to dry out more quickly. Also, keep plants away from cold air from doors or windows. Exposure to low temperatures can result in leaf drop and/or damage to the foliage. 
 
Humidity: Humidity levels in the home are usually lower in the winter than in spring or summer. While many houseplants are not affected by this change, plants such as ferns and orchids may perform poorly or exhibit brown or drying foliage. To combat this issue, place pots on rocks in trays of water to increase the humidity around the plant.  
 
Pests: Pest issues can also be a problem during the winter months. Click on the links below to learn more about the most common indoor pests and how to remove them: 

Additional Resources

 

Seasonal Gardening Tips
  • Set the pots of humidity-loving houseplants on trays filled with pebbles and water. Pots should sit on the pebbles, not in the water. 
     
  • Water houseplants with tepid water. Cold tap water may shock plants.
    ​
  • Fluffy, white mealy bugs on houseplants are easily killed by touching them with a cotton swab soaked in rubbing alcohol.
     
  • Check stored summer bulbs such as dahlias, cannas and gladioli to be sure they are not rotting or drying out.
     
  • Apply mulches to bulbs, perennials and other small plants once the ground freezes, to prevent injury to plants from frost heaving.
     
  • Avoid traffic on frozen lawns as this may injure turf grasses.
     
  • Limbs damaged by ice or snow should be pruned off promptly to prevent bark from tearing.
     
  • Use salt with caution or not at all around plants to prevent salt injury. Damage may not be evident until late winter or spring as temperatures warm.
     
  • Seed and nursery catalogs arrive. Begin planning your garden for the spring.

    Learn More
Enjoy the fragrant blooms of the Ozark Witch Hazel flowering in shrub borders or wooded areas on warm sunny days.
Repot any root-bound house plants now before vigorous growth occurs. Choose a new container that is only 1 or 2 inches larger in diameter than the old pot.
Repot any root-bound house plants now before vigorous growth occurs. Choose a new container that is only 1 or 2 inches larger in diameter than the old pot.
Blog & Latest News
Bloom Time Calendar

See when plants bloom at the Garden:

Gardening Help

We have staff available to help you with your gardening questions:

  • Plant Doctors: Master Gardeners and Garden staff can answer your questions in person

    Center for Home Gardening
    Every day, 9 am - 4 pm

     
  • Horticulture Answer Service: Have your gardening questions answered over the phone

    Mon.-Fri., 9 am to 12 pm
    (314) 577-5143
     
  • Plant Information: Email your gardening questions to: 

    plantinformation@mobot.org

    We are currently experiencing a high volume of emails, 
    therefore response time may be delayed. We thank you for your patience and apologize for the inconvenience.