Do you have a photo of the plants?

You want bright indirect light, water well when dry, or close to it.Make sure the pots aren't too large for the plants and both have good drainage. You might want to check for pest to be on the safe side.

Billy Rae

Aside fom Billy Rae's good points, do the pots have drainage holes? It's an absolute must that they do.

My spouse has pathos thriving in a guppy tank, leaves, roots everything under water.

Elsewhere on this forum, today on this page, someone is suggesting dracaena can be grown in water. Spouse is going to try that in a guppy tank also.

The pot has drainage holes and I check the water requirement before i water them. Might need to use fertilizer....what kind?? ANd yep no bugs. It has started sprouting small leaves but they are too tiny and i am scared that eventually they too will turn brown....what to do with diffenbachia?? Same problem.. I tried keeping them in shade and also tried the other way round by exposing them to indirect sunlight. But no positive change.

STOP all ferterlizing until the plant is growing in earnest.
It wont grow much at this time of season, the sun is very low ---the winter solstace, the shortest day of the year is approaching....and after that takes its time to resume what plants prefer. Wait until mid February/March to resume feeding.
NEVER feed a sick plant, that only exasperates the problem.

Put your plnats into good light...even direct sun but be careful about how the sun comes through the window glass...it can burn even in winter. Don't allow it to touch the window glass...its too cold and the leaves will feel it.

WAter to drainage, dump the excess after 5 - 10 minutes...allow the plants to dry down somewhat...but rely on how the plant prefers its soil...dry somewhat or damp.
Allow the water to sit overnight to gain room temperature and allows somewhat some of the fluorine to dissipate out of the water.

Dracaena especially does not like fluorinated water. For this plant you are directed to use another source than out of your taps. Bottled water, or melt some snow, is preferred and let it gain room tempeature.
The reason for this is tap water has a certain amount of salts in it. Dracaena reacts to such salts very quickly.
So over time, as you water it, the plant is taking up such salts and soon will show its effects.

Fertilizer you gve the dracaena should not have the ingredient "superphosphate" in it. Like the tap water, the plant reacts to such phosphurus source.

Generally, plants suffer from overwatering more than all other causes combined.
So let your plant dry down between waterings and always, water to drainage, dumping the excess after 10 minutes.
STOP all fertilizing until the plant resumes its health.
Never think to give it a pinch. Give it nothing but good care and warm sunshine....and STARVE IT.

What great and thorough advise, jeannie7. I'm printing your answer for my houseplant file. Thank you.
Pat
Michigan

Chlorine in a open jug of water will dissipate, unfortunately, fluoride will not, another cause of brown tips can effect certain plants, but not all.

If the pots too large for the roots, the roots can rot due to so much wet soil around the roots and/or have trouble growing, ending up staying small and weak. In the same situation, the roots can dry out because they are close to the surface,
Both wet or dry too long can cause brown edges.
If you place the plants in snug pots, you will see a difference in the plants health and growth, providing the soil is well draining and the light is sufficient.

Billy Rae

I inherited my Dracaena from a friend. It did well for a while. Now, the new growth on the underside is dying. Also, I've read that these plants like to be in "tight" pots. My plant has four main branches and is approx 1.5' tall. The pot it came to me in is 4.5" tall and 9" in diameter. Does it need to be re-potted into a larger pot?