Question
This morning I found a page I'd photocopied from a library book "Houseplants A to Z" saying "clean leaves with tepid water." It'd been over a year since I had done this with my 2 Ds (I propagated one from the other years ago), so I wiped the top surface of each leaf with a clean, moist sponge. Surprisingly, they weren't very dusty. Questions:
1)Does allowing dust to accumulate on the surface
of the leaves diminish their oxygen output? 2)What
is the thin, white flaky material--I wiped it off-
along (near) the edge of several of the leaves?
3)These 2 plants have been quite long-lived & healthy (I water every 2 weeks with a few drops of
"Schultz 10-15-10 Plant Food Plus" & have added some potting soil a few times over the years when the soil settles. Is there any reason for me to re-pot, ever?

Answer
Hi David,

Some locations are dustier than others. The best rule of thumb is that when dust becomes noticeable to you, then it is probably time to dust.

1)In general, plants breath through the pores in the undersides of their leaves where dust does not accumulate. However, the light sensors are on the top sides of the leaves. A heavy build up of dust can reduce the amount of light available for the plant to use. That is the reason to remove dust.

2) The thin flakes are the residue from water droplets (including dissolved minerals) that were emitted when the leaves first opened up. The flakes are completely harmless and can be removed or left alone, as you see fit.

3) Unnecessary repotting is the single most common cause of plant failure. Most houseplants max out in their pot size after a few years. If you find that the soil is drying out every couple of days following a thorough watering, then it might be wise to repot. Otherwise, it is best to leave well enough alone. Your fertilizing regimen will replace any nutrients that may be depleted over time.

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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