You may have a Kansas State extension office near by where you can ask for assistance. They have a soil testing lab. A place like this will tell you exactly what is wrong. It may take a year or two to get you soil into shape. But if you start now... 8-)

"wilty vines" sounds like now enough water? But that's just a guess based upon your word choice.

Here is a link that might be useful: K-State Agronomy Soil Testing Lab

PS - I've not had my soil tested yet (in Indiana) but I add as much organic material as I can to this darn clay. I add composted tree leaves annually, I add horse manure annually. My garden is not a raised bed, so it "doesn't get full".

And air is necessary for roots. Compacted soil is not good, turn it over every year. Gardening is all about the soil.

Boy, I thought every square inch of Kansas was ten foot deep ideal topsoil. That's what the wheat fields I worked in (for one day!) there were like.

But apparently not. I agree with clay dirt, if you have problems with plants thriving and the soil is clayey and rocky, then compaction and lack of air is the likely problem.

Well, maybe a little more info about the plants you are trying to grow will help also. Peppers: they like it hot. And even then they are slow growers. You say it han't been that hot yet, so nutrients aside, they likely would be growing slow anyway. Bell peppers have very poor yield for their size, at least compared to hot peppers. There is a Hot Pepper Forum, do some reading there, look for threads with newbie questions and bell peppers...

Potatoes: not too sure about Kansas, but here it is normal for potato vines to die off around midsummer. It is also common here to grow types that will not be trying to survive beyond midsummer because the ground generally gets too hot for potatoes to grow and thrive. So have you dug around looking for potatoes when the vines die off? Do you know how long your planted varieties are supposed to take to produce potatoes?

Corn: I've had limited experience growing it, but one thing I know is that unless you are planting the same type of corn and fertilizing it much as the farmers growing field corn are, you should not compare the size of your plants to theirs! It's not going to be the same. What matters is whether you get edible ears off of your corn. My corn is smaller in stature, but I got more ears for harvest than we could eat fresh last year, so good enough!

Beans, if they are bush types and maybe even vine types should have enough time to grow if you start some new seeds now. And that's all I have time to get to today. I definitely would second the advice above, get the soil tested. Then you don't need to guess as much, and it is pretty painless and cheap. Cheers!

If I were you, I'd stay totally away from Miracle Grow for anything in the ground. It inhibits natural processes, good insects, worms, etc. and the way that your soil will interact with the plants. It sets up a "false environment" where the plants in that soil will become dependent on it. When you stop using it, they will have a harder time surviving.

Organic compost, manure, etc. is the best way to go.

If you are using containers, it's not nearly as bad.

You might want to lightly work the soil about 5 inches from the base of each plant with a pitchfork or fork and then water lightly. Soil compaction is a big reason for early plant deficiencies.

BTW, three to four foot tall corn is normal for sweet corn. And sunnibel is right, worry about ear production, not height.

I don't know where you are in Kansas, but maybe conditions are not too different from mine. I live in the NE corner of Oklahoma.

In our climate three things are extremely important, soil, timing, and water.

As someone told you above, it is the nature of the potato to die off. The plants will turn ugly and yellow, die back and fall over. That is when you know they have finished their growth cycle and will soon be ready to harvest.

Onions are a very early crop here and I put plants in the garden near the end of February for bulbing onions. If you are planting from those little sets from the big box stores and only expect to get green onions, then you can get by with a later planting date. I would suggest looking at the Dixondale Farm shipping chart for your zip code to determine the date they ship to your area because after years of experience they know the best planting dates.

http://www.dixondalefarms.com/shipping

Onions are day-length sensitive so if you want bulbing onions, make sure you are buying the right type for your climate. I normally grow only intermediates and they have all been harvested and dried for a couple of weeks and I brought them inside today. This year I experimented with long day types and they are still in the garden and growing. We have had an unusually dry year and my onions are not as big as they should have been, so the ones left in the ground are being watered a little better.

I start pepper and tomato seed inside under lights at the same time about the 15-20th of February. I put the tomatoes in the garden after my average last frost date, and considering the current weather and the forecast 10 days out from that. Sometimes you will still have a chance of frost after that, but they are still small enough to cover at that stage. It is important to get the tomato plants in the ground early so they have time for fruit set before our horrible heat arrives, but since they are sensitive to low temps you have to protect them from any chance of frost when they first go into the garden.

Peppers - Although I start the seeds at the same time as tomatoes, I wait at least two weeks longer before setting out peppers. If exposed to low temps even for a short time they may be effected for life. They thrive in the heat and will produce heavy so be sure to cage or stake them at the time of planting or shortly after because a heavy fruit load may cause them to fall over, especially bell types. They can get heavy enough to pull the roots right out of the ground when they fall over. Most of the colored peppers grow as green peppers and it takes several more weeks for them to change to the ripe color. You will get more production if you use some while green because the plants will bear fewer peppers if they stay on the vine to the ripe stages, but that's your choice.

Cucumbers are heavy drinkers and heavy feeders. I try to plant them in the richest soil in my garden. Remember heat eats compost, and heavy rains leach out nutrients so you need to feed the soil every year. When the weather is hot a leaf will sometimes look wilted during the day, which it does to protect itself from the heat. If the wilted condition remains after the sun goes down then they aren't receiving sufficient water.

I plant both bush and pole beans and usually at the same time in Spring. The bush types will produce early and give you an early, heavy crop for a few weeks, but after that they aren't worth keeping in a hot climate in my opinion. By the time they are finished, the pole beans should be producing and if kept watered, they will produce until frost. Some years I skip the bush beans, but if you want to can or freeze for later, then they are a good choice.

With squash, insects are frequently a problem, and they can be squash vine borers, blister beetles, or squash bugs along with a few others. This year I kept mine covered with row cover until they bloomed, and although I still killed a few squash bugs, and squished a few eggs, I still have plants. Most people plant every few weeks so they always have new plants coming on when the first ones die. For winter squash, try to choose the most resistant types, like butternut.

I don't grow corn because I have only a backyard garden and not a field. I think it takes too much room for what you get from the crop. I know a corn farmer. LOL

Flea beetles and Japanese beetles may also be a problem and, if so, you will begin to see holes in your leaves, so be aware of that. I usually have a very hard time growing eggplant, but this year the flea beetles haven't done much damage to it. So far, the JBs have not been as bad as they were the last few years.

This fall, find all of the leaves you can carry home and try to cover your ground with chopped leaves for the winter. In Spring, pull them back and plant (if they haven't broken down), then after your plants are up and growing and the weather is warming, you can push them back toward the plants as mulch. Make all of the compost you can make.

It sounds like your plants need more water, but their water needs may decrease as your improve the condition of the soil in years to come.

If you think your soil is the problem then you might try buying commercial POTTING MIX and try a few things in containers. Use large containers if possible and be prepared to water often. I rarely use any fertilizer except in the planting hole when I plant tomatoes, but I feed my soil with leaves, mushroom compost, and the composted waste that comes from the chicken pen.

I hope this helps.