Desiring to bring your summer plants indoors? Plants that are not winter hardy in your area and are desired to be brought inside treated as houseplants are best taken in preferably during late summer to early September well before temperatures dip below 50°F. This will prevent cold damage to tender tropical and semi-tropical plants.

It is also preferable to acclimate and properly prep plants to the lower light levels of the great indoors before placing inside following these helpful steps.

While outside, move plants to a shaded part of your garden for about a week to acclimate them to lower light levels to be experienced indoors. During which time, inspect foliage, topsoil debris, and container/saucer for any uninvited pests. See cleaning prep below.

Watch nighttime temps during the five day outdoors low light acclimation period especially if plants are still outside in late fall. If temperatures drop during the five days below 45 degrees, cover plants with an old sheet or similar cloth to protect. After the five-day period outside, and proper cleanup bring plants indoors situated well away from your currently residing treasured houseplants avoiding infestation and disease problem from the newbies.

Once the plants are brought inside, keep in mind they will not require as much frequency of watering during fall and winter compared with the warm growth seasons outdoors.

Generally, depending on the plant only water when the soil is dry to the touch, ½ “- 1” below top of soil, more woody plants may need to dry out 1/2 of the entire pot's soil between waterings. Check cultural care requirements for each plant especially light, water, humidity and temperature. When watering, use tepid water early in the day not at night.

Plant prepping involves cleaning, grooming, and checking for unwanted hitchhikers deterring infestations and disease problems impacting all houseplants.

In addition, trimming may be needed due to faded foliage or to reduce plant size as required by using a sterile pruning tool. Always, clean cutting tools between plants. Also, cleaning the exterior of the container/saucer with soap and water is best. Not a good time to repot during winter's slow growth period. While outside, water plants well when going to dry, let drain, tossing excess drained water before bringing indoors. Check each type of plant for its watering needs.

Insect examination - Check plants thoroughly for any insects such as aphids, mealybugs and other invaders, remove with a water hose spray or by hand, drop found insects in soapy water and discard. Check for pests under and over the leaves, as well as the stems where insects most likely hang out. If stuck on insects are found, such as the common hard covered scale (small tan oval shape) rub lightly with a damp paper towel to remove (they can leave a sticky residue on leaves/stems spreading widely). Next, remove topsoil to freshen it up removing an inch or more of spent soil replacing with fresh potting soil preventing insect larvae from developing. After removing any insects found, follow up by using an organic safe insecticidal soap spray to be applied as a control and preventative, following label instructions; usually spray once then again after a week or 10 days later, inspecting periodically, well again and again. If a plant is overwhelmed with insects and disease best to toss out, then to subject present houseplants to problems.

Humidity needed - Indoor humidity levels can be very low, as compared to outdoors, especially when the heat is turned on causing plants to experience drying leaves, etc.  Not all plants require higher humidity. Humidity can be supplied by simply placing a plant/saucer on a larger pebble tray kept wet (water halfway up into the small pebbles, available from a nursery or garden shop). Check water level in pebbles during the week keeping it halfway up.

Watering needs - Overwatering during the short days of fall and winter is probably the most common plant problem indicated by leaf yellowing. Watering is less frequently needed during the winter rest period for most plants. It can be a balancing act of watering less frequently and providing humidity for plants to thrive. Some plants prefer less or little humidity, such as cactus and succulents, so check cultural care for each plant. 

Light – Plants that prefer bright sunlight are best placed in a south facing window during the short days of fall and winter. Some plants can take morning light (eastern exposure) or bright shade out of direct sun. Check each plant for its cultural care requirements. For even growth, some plants need to be rotated a quarter turn each time you water or weekly to prevent stretching on one side towards the light. 

Temperature - It's best to keep plants away from heating vents causing foliage damage, showing signs of wrinkling and discoloration. Also, too cold temps can cause discoloration and leaf drop. Check window area for cold air leaks. If the only source of light is from a window with a heater below. You can possibly deter heat below the plant with a tray placed under the plant or over the heat source.

Plant fertilizer is usually not needed during the slow growth period of fall and winter, well, depending on the plant, some flowering plants need ongoing dilute plant food such as orchids.

Courtesy of NYBG Plant Information Service / Mertz Library 

To check plant cultural care information, contact us at: plantinfo@nybg.org