WICHE: Acclimate plants as they move outdoors

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By Jeneen Wiche

I am particularly anxious to move some of my houseplants outdoors this spring.

The gardenia that I have had for more than 12 years looks terrible!  It needs the restorative environment of the great outdoors:  more light, warmth, higher relative humidity and rainwater.

I am not sure whether the cold house during the January ice storm/no electricity episode has had an impact on it or if it was just coincidence that it began to die back shortly thereafter.  In any case, it needs to be pruned up and sent outside to recover.

We winter over all sorts of plants from year to year: angel wing begonias, agapanthus, dipladenia, frangipani, ferns and a growing collection of succulents that spend the winter in a restful state in the windowed basement.

I’ve had zero pest problems (yes, this means no scale, white fly or mealy bugs…I stand by my belief in neem oil as the best botanical pest control for treating plants in the fall before you bring them indoors), so at this point all I need to do is get the plants trimmed up, repotted if necessary, fertilized and acclimated for their summer holiday outdoors.

First things first, if a plant has a woody habit (like many aged tropicals do), trim up the oldest parts, reserving the most vigorous parts of the plant.  Shape up the rest, making your cuts just above nodes where new growth is emerging.   I have a tendency to cut away more then less, but don’t be bashful. Once the plants are outside and it gets hot and humid, tropicals are in their element and will respond by putting on lots of new growth.

This is where fertilization will help, as well.  A diluted solution at watering time every couple of weeks is a good way to deliver extra nutrients to a hard working plant.

If plants have clearly become too big for their pots or there is more root mass compared to soil, then you may consider repotting.  Bump the plant up only one pot-size larger and use a potting mixture that reflects the needs of the plants.

For instance, a succulent will prefer a grittier mixture that drains well; a gardenia will like a potting soil and compost mixture that will provide extra nutrients and retain some moisture. 

Probably the most important thing to do for our peaked-looking plants is to take plenty of time transitioning them outside for the season.  Do it slowly because the sun this time of the year is hotter then you think, and when a plant moves from the filtered light of a sunny window in the basement to the full sun of the porch, the foliage will get burned up in a matter of a couple of hours.

Take several weeks to acclimate your plants to the direct rays of the sun.  Some plants can replace foliage at a faster rate then others; some only do it once a year. Don’t burn up these because you will have to wait several seasons before they can recover. 

All of this applies to your leafy houseplants, as well, although they typically require less pruning clean-up.  If you move them out, be sure to do it extra slowly, though.

Tropical flowering plants typically have glossier or fuzzy foliage that can withstand bright light a bit better then the thinner foliage of plants like the peace lily and pothos.  The average leafy houseplant will do well if it is located where it will get filtered light all day or morning sun and afternoon shade. 

I have a tendency to group plants near the water spigot for easy watering throughout the summer.  If you have problems with critters digging around in your pots, try putting pine cones, terracotta pot shards (a good use of broken pots) or a few strategically placed mid-sized stones (a good use of pretty stones you may have collected on our travels) to prevent easy scratching.