Product description and varchar field

[vis18neu]

I see in database that detailed (long) product description is a varchar field. We need much more space for description but it  gets cut off. We tried changing field properties according to advice at https://srihosting.com/blog/2012/08/virtuemart-2-product-description-field-cut-off/?Itemid=223. However, most recent upgrade to VM 2.0.14 reverted database field to old settings.

Is there a way to increase field size for detailed product description and to maintain that size regardless of every VM upgrade?