I keep planting hollyhocks from plants that are already started but they won't grow or come back the next year. The plants are grown from nursery stock. What's wrong? I remember them growing everywhere as a child.
It may be too cold for them. If they do not come back where you are, you may want to consider collecting the seeds for replanting each season. Under ideal conditions, they will often reseed themselves. Here is more info on growing this flower: https://www.gardeningknowhow.com/ornamental/flowers/hollyhock/tips-on-hollyhocks-growing-hollyhocks-successfully.htm
I have found hollyhocks have a mind of their own. I planted one a few years ago and it grew very well and flowered. After a couple of years for some reason or other it didn't grow again. However, another one grew about 7' away from it that I certainly didn't plant. It also grew and flowered for a couple of years. This year it has sprouted but it doesn't look like it's going to come to anything. We'll see. I remember them growing everywhere as a child too but that was in Scotland and any time I visit there in the summer there are tons of them growing. Could be our climate is so much warmer and humid.
Hollyhock has rust spots. What to do?
This article will help: https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm
I have not labeled a seedling and have hollyhocks and tomatoes seedlings in the same tray. How to differentiate?
When tomatoes get their true leaves (the second set of leaves the plant grows), they will look like small tomato leaves, which in most cases is the multi-lobed somewhat pointed leaves.
I've never heard of "Gardener's Delight" tomato. If it is an heirloom variety, it may not have the traditional pointy leaves of hybrid tomatoes and some other heirloom varieties. It may have what they call a "Potato Leaf". In this case, it will be harder to tell the difference between it, and other plants. Wait until it grows more leaves. If, after it has 6 to 8 leaves, you still can't tell the difference. pinch off leaves from both plants, crush them in your fingers (separately of course). The one that smells like tomato leaves is your tomato. ;) Good luck!
What causes rust spots on hollyhock?
This is called rust and is caused by a fungus. The following article should be of some help: https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm
Yellow spots under leaves. How do I kill this disease or insect larva?
Neem oil is effective against numerous pests and is a great fungicide as well. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
This is the third year my Hollyhock has brown-yellow spots on leaves and stems and I can't get rid of them with Sevin. Planted four new ones about one to three feet away from the old one and they got this disease right away. I don't know what it is. Can anyone help me out? Thanks.
This is likely rust fungus. Here is an article that you may find helpful: https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm
Do I cut down or pull out old hollyhock stalks at the end of their season? Does it make a difference how I treat the hollyhocks since I live in Phoenix?
You can just cut them back during your fall cleanup. Oftentimes these biennials will return, especially in warm areas like yours. You can also keep some seeds for replanting next season just in case. Here is more info on growing these plants: https://www.gardeningknowhow.com/ornamental/flowers/hollyhock/tips-on-hollyhocks-growing-hollyhocks-successfully.htm