That's normal. I have a few chinese evergreens and they all get that. I believe it's nothing more then dried sap. The mealies will be fuzzy, and you'll find a pile of cottony fuzz where the leaves meet the stems. It's good that you pay attention, because mealy bugs can get down right nasty if they go undetected for any significant amount of time.

Joe

That is good to know that it is normal. Quite familiar with the mealy bugs from my cacti collection and have had "nasty" experiences with them. Constantly checking for any new outbreak.

Thanks for the response

Jazz

Many plants, especially aroids, which aglaonema is, are prone to guttation. It is the process of xylem sap seeping out of stomata (pores) on the plant stems and leaves. It is normally mostly water with various salts and sugars dissolved in the fluid. The water will evaporate and leave the minerals behind and can form crystals.

It is a normal process.

Danny

Jazz, for some reason, Mealy have taken over from late 2010-2011.

Did you rid the Mealy on your Cacti collection? If you suspect they're in hiding, (eggs) isolate or keep a far distance from your other plants.. Toni

Toni

Had a mealy infection on the cacti this past winter. No mealy on the cacti for last month but still checking them over very closely ever 2nd day. Will continue this for the remainder of the summer at least. The Aglaonema isolated from the cacti.

Jazz

Jazz, what did you use to rid Mealy? Toni

Toni

Just spraying with mild dish detergent and picking off with a "mealy stick" (my name but just a piece of wood with a pointed end to get at difficult areas on a plant). Also, an old tooth brush is a big help.

Most important is to monitor continually each day for several weeks. As mentioned previously, I am at the point that I now look at ever 2nd day and will until end of summer or even longer. Have read that mealy larva can pop up weeks later and I believe it. (At this time of year my plants are outside on an apt balcony, so will continue to inspect.)

Don't mind the attention / time it takes because love being around the plants. Also, don't care for pesicides so that is one reason why I went the route I did.

Jazz