Question
I elected to take care of three plants hanging in 1/2 plastic bowls on a wall at work.  They were originally from a commercial grower.  The commercial grower came to the business about once every week or two and took care of the plants.  However, our business decided that money was too tight and discontinued having the commercial grower come to take care of the plants but they kept the plants.

I replaced the pothos once.  They were full of very small black bugs.  To my knowledge the bugs were there due to rotten roots.  I have been even more careful that the top of the soil is dry before watering.  

Should I try to leach out the salts and if so how.  Or should I take them out of the containers and remove the bottom dirt.  If I put in new dirt what would be recomended.  The commercial grower had small round white pellets in the very bottom.  

Basically they have florscent lights there is no direct light.  How should I fertilize them. The new leaves are much smaller.

I really do enjoy these plants.  I particullary like decorating them.  In the summer I put dahlia blossoms in them.  In the winter I put silver or white branches with glitter in them.

I hope to hear from you.  

Answer
Hi Bonnie,

Taking care of plants in offices like yours is what I do for a living.

Watering plants that are potted in planters without drain holes is a very tricky business, primarily because if you apply a bit too much water, the water will accumulate and gradually build up and rot the roots. In addtion, soil salts cannot leach out, as you pointed out.

The professional solution to this problem is to keep the plants in their original plastic grow-pots and put the plant and pot inside the half-pots. That way if you accidently overwater you can simply remove the plant and pour the excess water out of the half-pot. This also resolves the soil salts problem. This is an option you should consider if you need to replace any of the pothos in the future.

For the existing situation I recommend the following:

Get a wooden dowel that you can push into the soil right to the bottom of the planter. Remove it and see how damp the soil is at various depths. If the dowel is very wet at the bottom, that tells you that water is building up and you need to reduce the quantity that you add when you water. Pothos are reasonably drought resistant and the soil can dry to a depth of 1 to 2 inches from the top before they need water.

Do not fertilize. Fertilizer is a source of soil salts so it will only aggravate the soil salts build-up problem. Besides, in moderately low light, pothos do not need fertilizer anyway.

The leaf size is related to the light - less light, smaller leaves. The fluoresecent lights will keep the plants alive and healthy, but the plants will gradually replace their older (larger) leaves with smaller ones.

In order to keep the plants from getting stringy, it is important to prune back stems when they get too long. When pruning, cut the stem back close to the edge of the pot. The new growth will then emerge at that point, which is where you want new growth to come in to keep the plant full and compact.

Please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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