Why does my zucchini have yellow rot on it?

Question

I transplanted a zucchini plant a few months ago, and it grew to be huge. Then, a couple of weeks ago, i noticed a lot of my flowers and leaves were dying. I went out to check it out, and there was yellow rot with black dots all over the area where the stems came together, which was causing the stems to rot off of the plant, killing the leaves and the flowers. I don't know what this is or how to fix it, if i can. Any help?

Answer 1

Not knowing where you live, how much rain you get, and the like: I can tell you it's a fungus, but not what type.  

Unfortunately, if it's on the stems and doing what you describe; its a gonner.  Not news I usually like to give, but in this case....sorry.  You say you transplanted it....did you buy it somewhere else?  Did you check the soil before you put it in your own??  

Fortunately, most fungus' can be handled the same way, and the summer isn't over yet!!  You can still get zuchinni!!  Now....dig the plant out and dispose of it...do NOT compost it!!; till the soil under, till in funguscide (there ARE organic fungacides, just look for them!), manure, and composted humus....... and re-plant.  (ok. readers......don't jump on the reply train with scathing sarcasm yet....you CAN replant!!  just keep reading!!)

It's not too late (unless you live in New England or the upper midwest!), and by starting now, you'll be post season for the little critters that love to spread the majority of the fungus', avoid the squash beetle (which was probably the culprit since it started with the wilting blossoms)....and still have enough time for squash to make it to your table.  

Make sure you till in lots of peat humus....this will increase drainage and limit the amount of water to the active fungus spores;  you "mound" the soil, so that it drains properly (improving the likelyhood of the bottom of the plant/leaves NOT getting another fungus from the dirt), make the mound about 2.5 ft across and 12 " hich; put 3-4 seeds, evenly spaced from each other, about half an inch under the dirt, around the mound about half way up, and put shredded mulch on top of the mound and around the mound so that the leaves won't be hanging out with the "spores" that will still be in your soil.   The leaves/plants can and will push through shredded mulch (about 1/2-1 inch of mulch; hence proper planting depth)  

Do NOT overwater!!  And only water in the morning.  If you really want to control the water: they make red clay tubes that are open on both ends; you insert  it in the top of the mound and only fill them up/water through them....  If you can't find them, take a two liter bottle, cut off the top and bottom and use the same way!  Just remember to remove them at the end of the season and recycle!

Fungus LOVES wet, humid nighttimes and small puddles of water!

Most people won't re-plant immediately in the same area where they've had a fungus, but I've found that if I want that product, it's the only place that I have, and if I actually go out and take care of it properly (ensure drainage, etc...) that it works!!

Good luck and Happy Gardening!!

Answer 2

...or you might be overwatering...might be...

Answer 3

What you're seeing is normal. Zucchini plants, like all members of the cucurbitaceae family (melons, cucumbers, squash, etc.) produce male and female flowers on the same plant. During the initial first flush of flower production, usually only one gender of flower (usually the male flowers) is produced. These flowers naturally shed their pollen and drop off.

After this initial flush of flowers, a second wave of flowers develops that will contain both male and female blooms. If the female flowers on your plants (the flowers with the slight swelling below the back of their petals) continue to drop off once both types of flowers are being produced, it's an indicator of pollination problems (the female flowers will abort if not pollinated).

Usually, bees will take care of pollination, but sometimes you may need to consider hand-pollinating. You can use a Q-Tip or a long, thin paintbrush. Just take some pollen from the male flower and transfer it to the female flower and you will definitely have zucchini this year. Good Luck!