QUESTION: My potato plants are not flowering. How do I know when to harvest them? Do potato vines have to flower before harvesting? Or does it depend on the type of potato? -Matt G
ANSWER: Don’t worry if your potato plants aren’t producing blooms. The flowers are not needed in order for the plants to grow delicious tubers underground. Instead, the blossoms are linked to production of the small, green above-ground fruits that resemble tomatoes. Despite this resemblance, the fruits of the potato plant are poisonous and should never be eaten. They contain a toxic level of solanine, a poisonous alkaloid that forms when parts of the potato plant are exposed to sunlight.
Solanine is the reason parts of the potato tuber turn green when they are in contact with sunlight. These greenish parts of the potato must be cut away before the potato is consumed. All above-ground portions of the potato are poisonous and should not be eaten, including the flowers, stems, leaves, fruits, and any tubers that remained above ground. Consumption of parts of the potato that contain solanine can cause confusion, diarrhea, digestive discomfort, drowsiness, vomiting, shortness of breath, and weak or rapid pulse, and if solanine poisoning is not treated, the person who consumed it can die due to respiratory failure.
If you grow potatoes and your plants didn’t bloom out, you may be wondering how you can tell when you have mature potatoes (Some gardeners recommend waiting for the flowers to fade away before digging up potatoes.) In home gardens, the best way to know when it’s harvest time is to watch for the foliage of the potato plants to wither, go dry, and fall over as a signal for you to start harvesting your potato crop.
What about potato Bugs ?
Captain jacks or BT early in the season
I personally had a Colorado Potato bug problem in past years. Initially I hand picked them off the plants and tried to find and remove the orange egg groups from the bottom of the leaves. However, eventually you miss some and they multiply rapidly. If left unchecked, they will eat most if not all of the leaves on your plants and reduce or severely limit the production of potatoes. Once they seem to be causing significant damage, I use Sevin Dust to kill them and if it rains, you will need to reapply. It works if you can apply before the damage is done. If you come in contact with the dust, wash thoroughly and do not breath in the dust (use of an old Covid mask seems to work).
Thank you for this info. I have grown healthy looking potatoes that haven’t flowered so this information was really helpful.
Good info to know! The deer have been eating the flowers on my potato plants and I was concerned that the potato would stop growing without the top part of the plant .
My potatoes are not blooming so I dug up a few and it seemed they were just setting tubers, we have had a lot of rain and the ground is still saturated so I will try to be patient.
Some potatoes, like Kennebec and Russet Burbank, are sterile and do not bloom.
Would coloured, say red or black potatoes, not produce solanine under light, or perhaps take longer to do so?
What if some of the green foliage of the potato plants dries out and another part does not? What should I do?
Thank you very much with these information l have grown potatoes these season and other have not blossom however the leaves have grown so big and l was very worried about blossom. The other matter is they are cracking and is like the tubes are going to be out but is not dry weather is raining in Lesotho.Thank you in advance
Try hilling or mulching around the plants. I also used leaves left over the the autumn. This helps keep any potatoes from getting the sunshine that turn them green and potentially poisonous.
I am a first time Gardner and I found your article very informative. Thank you
Good information thank you
This is a first for me (I am 70yrs old) that my potatoes have not produced any flowers ….. I am just waiting for the tops to die down a little cos I am anxious to see if there are any spuds to harvest, Fingers crossed
Dig one up & see.
Okey very helpful
If the leaves, etc. are poisonous why is it that deer eat them ?
First time trying to grow potatoes. I never saw any flowers so I was waiting for the plants to die back completely. I was ready to dig them out but realized they were growing new green shoots again. Is it to late to harvest? Did I miss a window of opportunity? Should I wait for them to go thru another growing cycle?