There are a number of reasons why people plant the pots.

1. It's a good way to winter a potted rose. The ground does provide good insulation.

2. It's a protection against voles or moles or whatever from eating the root ball.

3, You can temporarily plant the pot to see if the rose will grow in that spot, i.e. enough sun.

There are probably other reasons as well but you get the idea.

However, I don't think it would aid in drainage for you. Even though the potting soil will drain better where will the water drain to? It will stay in that heavy clay soil against the pot and not drain away freely as it needs to. Eventually the pot will fill up and be too wet for the rose anyway.

I have lake bed clay soil as well and it is a problem but I just dig big, deep holes and hope for the best. I usually know right away if it's not working and there's too much water by the rose's behavior. Then I dig it out and try again. I did do some deep roto-tilling on the new bed we made and that seemed to help a lot with breaking up that layer of clay. The soil beneath it wasn't nearly as dense and with the clay broken it drains pretty well now.

Here is how to determine if your soil has poor drainage. Dig a hole one foot deep. Fill it with water then let that water all drain away. Then fill it with water again. Measure how much water has drained away this time after one hour. If it is less than two inches on the second filling, then your soil drainage is considered to be poor.

There are a number of things that can be done to improve soil drainage. The easiest is to add organic matter, which works best if the problem is merely clay soil. It is more difficult if there is a hardpan layer under the soil. In that case drains may be needed, or something that can rip through the hardpan layer and break it up. If this is all too much for you to deal with, you can simply plant in raised beds.

Rosefolly

Here is a link that might be useful: How to improve soil drainage

We do it because any rose not so-protected will be killed by gophers, which are a plague, here.

But I think it would increase your drainage issue.

Jeri

Rosefolly,

That hole is large enough now to be large enough for a small dog. At this point it would require filling it, re-digging the hole then starting the test. Thank you for the advice as what I may do, is during September, when I dig up a plant in the same area , but about 8 ft. down, I will attempt the test. I believe there is a drainage issue in the entire bed of clay.

Yes, planting roses in pots in the garden will make drainage worse.

Almost all the suggestions you will hear for improving drainage won't work because they don't address the question "Where will the water go?" The surefire cure for drainage issues is raising the bed. Just 6" will help.

To do an accurate percolation test, you must fill the hole and let drain, as rosefolly says, until the subsoil is saturated. Then fill again and start counting. Good drainage is if it drains 10 or 12 inches in as many hours

Another reason for planting in sunk pots is to protect the roots from oak root fungus disease in California.

Thank you all for the advice. With our primarily sandy soil, not much in the way of rodents; none underground that I know of, and with exception of caliche, which usually only causes problems during excavations for swimming pools, we usually do not have major drainage issues. I seem to be left with no option other than digging holes, testing their drainage. and solving the issue as there are very healthy vines and a large sago palm in this area.:( if they weren't there I would build a raised bed myself and call it a day.

Lynn

This post was edited by desertgarden561 on Sat, Aug 3, 13 at 18:21