Volunteer cape gooseberries saved my tomatillo crop last year. I didn't
know that tomatilloes were self-sterile; I thought they were fertile
like tomatoes. I only had 2 plants, raised from seeds harvested from the
same fruit. They bloomed for several weeks without setting any fruits,
and I was about to pull them up. Then the cape gooseberries that were
coming up everywhere started blooming, and the tomatilloes started to set.

Are tomatillos really self sterile? I didn't know that. I know that the
first few weeks I won't get fruit to set unless I get out there with a
brush and hand pollinate. That seems to work fine - a bit labour
intensive though. At some point bees and other flying insects always
discover them and I can stop hand pollinating. I had been planning on
not growing ground cherries this year because I'm almost out of
tomatillo seeds and wanted to save their seed this year and I didn't
want to risk it crossing with the ground cherries. Maybe I should
reconsider - DH would mutiny if I didn't make salsa verde!

BP