I suppose two basic questions need to be asked.
#1. How big is the pot and does it have a drainage hole?
#2. How much sun will the plant receive with northern exposure?
Everything you have planted previously needs 6-8 hours sunlight. A shaded front porch with northern exposure does not provide enough light for these conifers.
There are a other factors that could enter into the quick demise of the conifers but I think lack of sun is where I would place the blame.

Dave

Try Taxus à media 'Hicksii' or 'Green Candle'.

The pots will need to be a good size, whatever you plant, ideally at least a cubic metre of soil, and with drainage holes at the bottom.

Resin

but they shouldnt be filled with soil .. right resin ...

a home made mix of 50% mini chunks .... and 50% peat based soil less medium would probably work better ....

ken

There are lots of dwarf hemlocks in various sizes and growth paterns available and they should be fine in a pot as long as the drainage is OK.

Thanks for the info - I will have to look those up. The dwarf hemlocks sound good too, as long as they would be fine in a pot.

Dave, yes the pots do have drainage holes. They are 16 in. across... maybe we do need bigger pots? We just can't go too much bigger or they won't fit on our front porch. They don't really receive too much sun at all being on the north side. I would say maybe a just a couple hours morning sun, and the same for evening sun, just before sunset.

I really appreciate everyone's ideas! :)

For container mix for conifers I use very small pieces of bark ( like mini nugets but smaller). The nursery that sells this product calls it soil conditioner. Espoma has a prodcut called Clay Buster (I think) that looks like very small gray (pourous) gravel, also to help with the drainage is a white granite like product called Chicken Grit - sold at the farm stores. All four ( including some peat) make a nice well drained soil. A big drainage whole is great and I do not put gravel on the bottom - just a window screen. The soil mix is always discussed by Al on the container forum. In fact Al does not use any peat. He also include a product call Profile Turface, which is great but had to get in my area. I have used my mix in my hypertufa troughs with great sucess.

For any containers I like to use a conifer that is one zone colder - so zone 5 or lower. I agree with the taxus, for the best in shade. Maybe a tall Ilex crenata like Sky Pencil would work too. I have seen them grow in the ground in somewhat shady areas.

Mike

Thanks Mike. I did see the Sky Pencil and was considering that one!

As far as soil, I always just used regular garden or potting soil in these pots. Could this have been contributing to the problem? Are the products you are referring to used alone, or do I need to buy several things and mix them? I am confused about this part of it. I am hoping there is something already pre-mixed that I can just place into the pots without having to think about it too much or buy too many products. Thanks for your help!

Sorry for the confusion. I would mix using potting soil maybe 25%, grit 25%, the espoma product 25%, and the fine bark 25%. The link below from Al, may indicate slightly differnt mixtures. I like some peat moss in my containers he does not.

This link is one of the most interesting discussions on ingredients for containers that I have read. Have fun.

Here is a link that might be useful: Al's Soil Mix

No problem Mike. Now would I just mix all these together in the pot, or layer them?

I am not up on all the soils.. probably because I always try to keep it simple. heehee

Mix it all togehter---
The larger particles create air spaces and improve the soils ability to drain well.
These ingredients do not contain lots of nutrients, so you will need to fertilize. Conifers do not need lots of fertilizer. I might use a time released fertilizer. Others on the forum may have better ideas.
Containers are something that do require more attention than plants in the ground. Looking back at your original post - the aberta spuce should have lasted a few years in the container, even though the amount of light was not the greatest and the mites like to attack them. So if you choose to go through the trouble to mix a new batch of soil, and you purchase a new pair of conifers, daily attention and regular watering in critical. Mike

Thanks again for the info. And you are absolutely correct about the mites on the alberta spruces!! They look just lovely right now sitting on the front porch all brown (lol).

Just when we get some nice weather and I am tempted to plant something, we get hit with another snowstorm here!

Just an update... I planted the 'Hicksii' yews on my mostly-shaded front porch in the cement pots, and they have been doing great! By the way, do these like Hollytone or Miracid? Just wondering what I should give them (or IF I should give them anything). They have gotten lots of new growth, and I just want to keep them happy and well fed. :)

I'm guessing no fertilizer necessary (assuming those are fertilizers). You don't, after all, want a great deal of new growth, as you want them to stay to size for these pots. I also doubt they need it. By the way, yews take well to pruning so don't hesitate to trim as required.

KarinL

I have dwarf alberta spruce planted in a cement pot, and so does a friend of mine. I'm in Wisconsin. As long as the pot is big enough, and you are still providing some water over the winter months (when temps are above freezing), they should be able to survive the pot. I haven't had any problems. I also add mulch to the surface soil. Good luck.