[lacewing]

I have six blueberry plants which need to be transferred to larger pots. I want to sink them in the ground, as other plotholders have done. Bearing in mind the cost of large pots and a large amount of ericaceous compost, I am wondering if I could use heavy duty plastic bags instead of pots to reduce the cost?

[bigben]

There is a tension between getting drainage - (though blueberries do like it wet) and the effect the soil has on the pH of the ericaceous compost. Over time the acid compost ends up the same as the surrounding soil and needs stuff adding to it to maintain the acidity.

 This is easier to maintain in large pots but the downside is keeping it moist. You might be able to just bury large bags that have been punctured to allow drainage and fill them with ericaceous compost. You will still need to add stuff to keep the pH down but not as much as if you just plant the blueberries into a hole filled with compost with no barrier to the acidity changing.

[savbo]

My bluebs are in a trough, lined with old compost bags with some holes punctured, then filled with a mix of ericaceous compost and soil (to salve my conscience about how much peat I'm using - this is the only time I use it). We did lose a few though I think that was down to how they'd been grown originally - the 3 from another supplier are romping away....

so yes, I think bags would be fine

sav

[lacewing]

Yes, I think I will try digging out large holes and lining them with heavy duty plastic, has to be cheaper than buying large pots. The plastic should stay intact and will not rot, worth a try!
I have just dug out a very large fig tree, planted in a pot and sunk in the ground 8 years ago. The reason for the pot this time was to restrict the roots, or so I thought. On digging the tree up I found  the pot had split in several places, allowing rhe roots to escape.
Such a shame as I was getting heavy crops of figs. But it was in danger of taking over the fruit cage. I nearly lost an eye one day trying to get to the currant bushes.

[Trillium]

Before Gardeners World redid their site, they had a video clip of the host digging out a large area, lining it with poly sheeting, punching in a few drainage holes at the bottom, filling it with soil, then planting blueberries and cranberries in the 'enclosed' area. I've done something similar but in actual raised slab beds (since I can't dig down into my area). The beds are 18" high, filled with composted manure and peat, and the inside edges lined in poly sheeting with drainage holes in the bottom. The blueberries are loving.

As for the figs, root prune them every year in fall. This will contain their growth and give you the good yields.

[Growster...]

We popped ours in last autumn (with some ericaceous compost), and they get all the tea leaves, which surprisingly, amounts to much more mulchy stuff than we imagined!

The first leaves have just started to bud, so fingers crossed an' that...

[lacewing]

Thanks for the advice folks!  I shall get to work as soon as the weather improves. I can't wait to make blueberry cheesecake.
Growster, thanks for the reminder,  in some forgotten corner of my mind I did read that tea leaves are acidic,  the amount of tea we drink, I should have buckets of used tea bags in no time!    I love this forum!  

[Living in Hope]

We are planning to redo our bathroom in the next couple of months - would the old bath sunk in the ground retain too much moisture or could this become a blueberry bed?

[sunshineband]

If you ensure the plug hole stays clear to drain and you add a decent layer of gravel, it might be worth a try.

Or try making more holes in the base as well,  if it is not cast iron of course