potatoes?

I am relatively new to SFG and tried for potatoes this year. They are in fabric grow bags, 2-10 gal and 1-7 gal.  They were planted "on time": for our zone (7a) and looked to be doing great for some time, but now the leaves are falling off the stems and turning yellow/drying out.  Are they ready to harvest? Am I possibly overwatering?(until this week, we hadn't had rain in quite some time. I've been watering 2x per week and soaking them well)  They did bloom briefly a few weeks ago....but so far my "garden" isn't doing well at all, it seems. No tomatoes, no bell peppers, no pumpkins, no watermelon

Lisa, it sounds like they are ready to harvest. Bloomed and now dying. Stop watering to let the Mel's Mix dry a bit and then start panning for gold. Pull up the plant(s) and then gently finger dig around for lost potatoes.

Regarding other issues with your new SFG, give us some more information plus photos to help trouble shoot.

Well, I waited a few weeks and harvested yesterday. Not great, but not terrible, so there's that.  I got approx 2 lbs of potatoes from each seed potato...russet, yellow and red.
Also finally pulled my carrots and they were miniature too!  Not sure what happened, the carrots & garlic are in a self watering bed of MM (new this year) and the potatoes were in fabric/felt grow bags.  They were all planted IAW my last frost date (mid April-ish) and according to the package, the carrots should have been ready in June, but they look like they could have used another month! LOL

Ah well...onwards and upwards, now to decide where my black raspberries are going to live, so I can get them in the ground to overwinter, and hopefully give me berries next year!

Lisa, it’s been a rough year with the excessive heat, rain then no rain, etc.  None of my pumpkins made it either.  Peppers are OK, but lighter than usual yields.  I think it has just been a rough year, but I agree with sanderson, pictures would help.  Do you like radishes?  They are quick and make a nice fall crop!

Thanks so much! I actually don't have any pictures, it seems that every time I go out to work in the "garden" I leave my phone inside/upstairs!  I've essentially given up on the pumpkins, I have one tiny watermelon I'm hoping to baby through to maturity. The bell pepper admittedly went in very late, and never even bloomed. The tomato has given me I think 3 ripe tomatoes of which 2 were eaten by the chipmunks or squirrels, but still has several green ones yet.  Our last frost isn't until well into October, so I may let that continue to do it's thing as long as it will.

Sorry, no radish fans here.  I'm looking forward to pulling the peanuts, they were my experiment for this year.  I planted 4 seed in 1 grow bag (basically one SFG square), so we'll just see what they do.

I'm looking forward to trying to put in some kind of permanent trellis for the black raspberries, but the "back slope" where I intend them to grow is EXTREMELY steep-like break your ankles walking on it-steep, so I'd simultaneously need to do SOMETHING to give safe footing for around them.  Frankly, terracing that slope is more work than we are capable of doing, and would be more expensive than we can currently manage, so I have to find a happy medium.  I'm thinking pre-built wooden steps attached to posts?  and then posts + trellising for the berries. They are my husband's favorite for jelly & eating and I have 4 grow bags of 3 different varieties.  Fingers crossed!

Are you planting according to local guidelines? I tried to find a Knoxville County Master Gardener vegetable planting guide, but these were the best I could find.

https://extension.tennessee.edu/publications/Documents/W346-B.pdf

https://garden.org/apps/calendar/?q=37205

Thanks for those!  Info I had was that our last frost was expected mid-April and first frost expected mid-October, which mostly lines up with your info.  It got very warm here, very early this year, then we had weeks of little to no rain (my water bill   ) and now we've had a TON of rain the last 2 or 3 weeks.
I plan to blame all of that for my poor harvest...it couldn't possibly have been MY fault! lol