How do I trim my Philodendron that froze?
I would wait till spring to trim it. These articles will help you:
I have two large split leaf philodendrons that are about 5 years old and have been very healthy, but the foliage froze in our bad freeze this year (Austin, TX). I have pulled the stems from the main stalk, which feels like it is waterlogged in about the top third of the stalk. The stalk is about 5 inches in diameter at the base. Should I cut these back at the 'drier' point or leave them alone? Do you think they survived, or should I replace them?
Any part of the stem that feels "mushy" is dead and does need to be pruned. Stems that are still firm will regrow leaves. And it will regrow if the roots survived. These articles will help you as well:
I have an outdoor plant that has large tropical-looking green leaves and has a base from which long tentacle-looking legs find their way into the soil. I would like to know the name of this plant.
I would guess that it is a true philodendron (not a pothos, which is often mistakenly referred to as philodendron).
You may have a Monstera deliciosa. Look for an online image and see if it matches yours.
I have a Philodendron and two tropical plants that were in my kitchen bay window. I noticed a white powdery material on the leaves of the plants that were together, not on the ones separated. The powder was on the top and bottom of the leaves but was easily removed when wiped with a damp cloth. What could this be?
Neem oil will work well on powdery mildew problems. You can read more about this oil here: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
You can also find other home remedies for powdery mildew here: https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm
If the white stuff is soft and cotton-like, then it is a mealybug infestation. Treat it by thoroughly by spraying with a solution of 5 parts water, 1 part alcohol and a squirt of liquid dish soap. The key is to spray all leaf and stems surfaces of the entire plant until they are dripping wet.
Why are the leaves turning yellow on my philodendron?
This article will help:
I have 2 houseplants, one is a new log or totem pole and the other is a philodendron. When I water sometimes, I pour some down into their stem, but lately there is foul odor like wet laundry that has set for weeks. It's a bad smell, only on those 2 plants. HELP. They still look good and healthy, their shoots just stink.
It sounds like the plants may have root rot and what you smell is the roots decomposing. There is not much that can be done to help the plants, but this article may help: https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm
They over watered it and this is what caused the root rot.
My Philodendron has been a healthy plant and grown a lot over the last year. Currently I have what appears to look like dry grass on the top and underside of some of the leaves. Any idea what might be causing this and what it is?
They are likely aerial roots. I would recommend providing something for these roots to cling to, like a pole of some kind.