I know the brown, curled blooms are spent, but I would also like to remove the blooms that are done opening - if they are actually spent. My question is: how do I tell the difference between an old bloom that is still colored but not open, and a new bloom that is about to open? Are the closed blooms in my photo "spent"? It is 2:30 pm mountain time and they have been in full sun since 9am.
I do believe the closed dark purple ones look to be spent blossoms.
If you look closely you should see the edges appearing drier than say new budding flowers.
If you leave them to fall off themselves they usually leave the stamen behind. You can then pinch that part off of the plant.
I like to use a small garden snip and trim them back to the next group of flowers.
Enjoy!
Here is a link about dead heading flowers.
https://www.gardeningknowhow.com/ornamental/flowers/petunia/deadheading-petunias.htm
https://www.gardeningknowhow.com/ornamental/flowers/fgen/deadheading-flowers.htm
I am noticing small holes being eaten in my petunia petals and echinacea leaves. They have not flowered yet, just planted this spring. I am not sure if I should spray with a chemical or have also heard Epson salt solution or mild soapy water spray. Please advise on best way to prevent insects from eating. Thank you!
We normally recommend using Neem oil for most insect pests in the garden. It is both safe and effective, and as a bonus doubles as a fungicide too. Here is more information: https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm
Petunias are yellowing and starting to die. They are planted in rotted cow manure with peat moss added. What would be some reasons as to why the petunias are dying?
Here is a link to help you.
https://www.gardeningknowhow.com/ornamental/flowers/petunia/petunia-care.htm
I've had them for 3-4 years. Always beautiful. This year the dead blooms aren't falling off.
I'm not sure of the cause, but sometimes our plants need a little help!
I would clean them up with a quick dead head and see how they act the remainder of the summer.
https://www.gardeningknowhow.com/ornamental/flowers/petunia/wave-petunia-plants.htm
I planted some very healthy supertunias a few days ago. They had been doing great and then this morning, they were laying over-seemed like they had been cut and were not attached to roots. Digging into the soil, I saw no roots where the plant was! Is this an insect that eats roots? What pesticide is best, and can my plants be salvaged? Will they re-root? The actual leaves and blooms were not bothered.
Petunias are usually pest free for the most part; however aphids and cutworms occasionally affect these plants. In this case, it sounds like cutworms may be the culprit, as they typically 'cut' the plants as you describe. This article should help: https://www.gardeningknowhow.com/plant-problems/pests/insects/get-rid-cutworms.htm
Hanging petunia plant that I bought has been shriveled and brown and yellow looking right from the beginning. Now it has gone 1/2 down all leaves are brown or yellow, but the bottom is green and blossoming despite watering it twice daily. I believe it needed a bigger plant pot maybe. I fear it will die.
It sounds like it may have a fungus. Trim away any yellow or brown growth and then treat the plant with a fungicide.
In May I decided to grow some petunia plug plants in my greenhouse. I planted them in cell trays and they grew really well and big. The problems started when I transplanted them to baskets, the compost just crumbled away from the plants, the roots weren't bound around the plants to hold the compost together. The plants were big so I couldn't leave them in trays any longer and I'm sure I watered them correctly. I've tried to grow plugs before and the same thing happened so what am I doing wrong? Is it the type of compost I use which is BQ?
Seeds and seedlings should be gown in a very light medium.
Here are some links to help you.
https://www.gardeningknowhow.com/garden-how-to/seeds/when-to-start-seeds.htm
https://www.gardeningknowhow.com/garden-how-to/seeds/soilless-seed-mix-info.htm
https://www.gardeningknowhow.com/ornamental/flowers/petunia/petunia-seed-propagation.htm