Problems with my vegetables

I started gardening earlier this year. There are some key issues I am experiencing at the moment:

• Desiree potato – I have 2 plants in grow bags & 2 in plastic pots. The plastic ones have some leaves yellowing at the bottom. There are some potatoes poking through the surface & have been flowering for a couple weeks – does this mean it will be ready to harvest soon? Or are the plants unhealthy?

The grow bags have remained roughly the same size for about 4 weeks, with some minor growth in the last week. They are the oldest plants being almost 3 months old, however, have not flowered at all & no signs of potatoes.

• Zucchini – The lowest leaves are very yellow & the higher leaves have some sort of white coloration & curling.

• Strawberry – There are dots all over the leaves, & the leaves keep dying. This has been ongoing for the whole year. No flower/fruits have appeared for a month, with the last fruit appearing in late November (is this due to the variety?). I split the plant & transplanted in mid November, so maybe that caused some damage. There's also ants that seem to be building an anthill at the base of both plants, not sure if that's harming the plant.