Zucchinis - fruit rotting

[Vanessa]

Hi everyone, My zucchinis seem to grow to a certain size (about 5cm) then start to rot from the flower end towards the plant stem. Sometimes there are maggots inside if I don't find the fruit for a while. I'm just wondering if anyone can help me to stop this. My mother-in-law told me to remove the flowers from the ends but this doesn't seem to be helping. I have only managed to get 3 zucchinis off one of the plants (out of 2) although they are producing many more I don't get to them before they rot.

[Jane]

Vanessa, As you live in Brisbane I would suspect that your zucchini are being stung by fruit fly, the grubs of which are small & white & can jump. I've not found much that helps except nasty sprays. You could try covering the whole plant with a fine net to exclude the fly or cover each individual fruit with a paper bag as soon as it sets.
Hope this helps
Jane

[Vanessa]

Thanks Jane, I'll give it a go.

[Donna McCallum]

Hi Vanessa, I had the may of the same issue before I gave up on zucchini in disgust this season and while I will try again next summer (and over winter) I am hoping to use luffa instead which is better suited to our climate.
I think there are two separate issues:
1. Maggots, this sounds like fruit fly, and you will need to use exclusion bags and/ or traps
2. Fruit rotting, I think this is a fungus disease. Not sure how to fix it, if you have obvious powdery mildew you could try wettable sulphur or milk/ water spray. Other than that try to keep the plant healthy and use seaweed fertiliser, and don't wet the leaves when you water the plants.

[organicjohn]

Not an expert, but from your description and my experience, this is 'blossom end rot'. You can probably get more information than I can give you just by googling the term. I believe it to be a result of calcium deficiency in the soil and thus use an annual application of garden lime to the beds to control it.

I suspect the maggots are a consequence and not a cause.