Vine Weevil Grubs On Fuchsia Roots?

This fuchsia was cut back almost to surface level last autumn and kept in its original compost. It seemed to be doing quite well until a week or two ago, when the bloom disappeared and it didn't look so healthy. At this time of year, the root damage caused by over-wintering vine weevil grubs in the compost becomes noticeable on plants. I would not expect to see vine weevil, since the compost and roots were treated with 'Provado Vine Weevil Killer' (9g/litre thiacloprid) in August; this should protect for six months so is probably about spent. Nevertheless, we cannot take a chance. Time to examine the roots.

Removed plant from pot and gently brushed away compost from around roots, trying not to damage them. No vine weevil grubs. So washed off rest of compost, just to make sure. Still no grubs.
There is very little new root growth. And what there is is not yet of the fine fibrous kind (this develops later) which fuchsias use for feeding. I don't know why this should be, unless it is a late developer (I haven't grown it before).

As to the loss of bloom, I could have damaged them in some way, though I can't think how. Although I might have recently given the plant a bit of dilute feed to help it along. This could have burned the infant root hairs. Seems the most likely cause. Will I ever learn?


Just out of interest, here is a different variety of fuchsia treated in an identical fashion. Look at how many fine white feeding roots there are. Note that they are growing from the old, thicker, brown root material which seems to be attached (I'm 99% certain) to the old, thicker, tapered, brown 'tap*' root on the right.


*A tap root system develops from the radicle, the first primary root to emerge from a seed.

Stem cuttings produce several primary adventitious roots around the stem, each of which produces lateral offshoots. When young, these roots are white, but as they get older, secondary thickening occurs (we haven't covered this yet) and cork material is laid down producing a darker brown root behind the area of the root hairs.

Plants do not take in water and nutrients through older wood, but through the root hairs, as seen elsewhere. These are very short-lived and exist only at the tips of new roots. It is worth bearing this in mind when growing plants, because it is this area which needs special nurturing; the older wood doesn't matter.