SpudPhD
Newly Registered
Posts: 1
Joined: Mon May 11, 2020 5:27 am

Soilless Potatoes

Hello, my name is Dom and I'm new here. I couldn't find a sticky for this board so hopefully I'm not breaking any rules.

I am a PhD student interested in (amoungst other things) trying to efficiently grow potatoes hydroponically/in soilless media.

As I'm not allowed onto campus at the moment, I have set up an experiment in my flat using coco coir as a growing media, suspended over a basin which will be filled with nutrient solution. I have never grown anything hydroponically before (except propagating herbs), but I'm keen to learn as much as possible before I spend my grant money on any big experiments!

If anyone can point me in the direction of any useful resources, that would be fantastic. And for more detail on what I'm trying to do, check out these videos my YouTube.



User avatar
Gary350
Super Green Thumb
Posts: 7396
Joined: Mon Mar 23, 2009 1:59 pm
Location: TN. 50 years of gardening experience.

Potatoes are a tricky crop to grow I have been growing an experimenting with potatoes for 42 years. If you do everything wrong you will still get at lease 1 potato per plant. If you do everything right you can get 30 potatoes per plant.

Be careful not to give potatoes too much nitrogen or you will get very large plants and not many potatoes. Best fertilizer is 15-15-15 about 1/4 lbs per plant. Every time you hill up potatoes put more fertilizer in the soil that you use to hill up your plants.

Very hard soil will prevent potatoes from growing large. You can spend a lot of money on soft factory made soil in bags and spend more money on soil than it will cost you to buy potatoes at the grocery store.

Potato plants like soil about 5.5 to 6 ph but they grow very well for me in 7 ph soil. Buy vinegar in 1 gallon bottles mix with soil to lower the ph. Buy ph paper $1 per pack to test your own soil. Peat moss sells for a reasonable price I have grown good potatoes with it tilled into my garden soil about 50/50 mix soil/peat moss. Straw works very well too plant cuttings in real soil then hill up the plants about 2 ft deep in straw little by little as plants grow taller.

Potato plants do not like extremely wet swampy soil they will rot. Calcium causes potatoes to have scabs.

Red potatoes will out produce white potatoes about 4 to 1.

Some potatoes like Kennebec & Red Pontiac grow very well on hot weather. Most other potatoes like cooler weather.

There are 2 types of potatoes, determinate and indeterminate. Determinate plants will grow a fixed quantity of potatoes about 3 lbs per plant. Indeterminate plants have the ability to grow more roots every place soil touches the stems. Every time you hill indeterminate potato plants up higher another 5" plants grow more roots and those roots grow an additional 3 to 5 lbs of potatoes. My potatoes plants this year are growing at a rate of about 6" taller every week. I have hilled my plants up 2 times the eyes are under 15" of soil so plants should grow about 4 lbs of potatoes every 5" that = about 12 lbs per plant. If I continue to hill my plants up another 10" plants should grow another 8 lbs of potatoes for a total of about 20 lbs per plant.

Buy seed potatoes no smaller than 2" diameter and no larger than 3" diameter. Look for seed potatoes that have 7 eyes on each potato. It is a waste of money and waste of potato to buy large 5" potatoes that only have 2 or 3 eyes. If you plant whole potatoes with 7 eyes each eye might grow a plant but sometimes only 4 or 5 eyes will grow plants. Potatoes that only have 3 eyes might grow only 1 or 2 plants. When making cuttings try to get 2 or 3 eyes per cutting. Make cuttings no smaller than 1" across for each eye. Let cuttings dry in the shade for about 4 days before planting them.

Keep seed potatoes warm and in the dark for 1 month eyes will sprout and grow long. I keep seed potatoes in the house 74 degrees F they are ready to plant in 1 month.

Most potatoes are a 4 month crop or very close to 4 months. Plants will blossom in about 2 months. There are no new potatoes in the soil until after plants blossom. Potato plants need full sun all day every day. If you live where it rains once a week all summer you will get larger potatoes. If you have no rain you can water plants once a week for larger potatoes. After blossoms plants start growing new potatoes. Last year I did an experiment 1 month after plants blossomed I hilled up a few plants then the plants blossomed again and started growing second crop of potatoes. When I harvested first potato crop was the largest, second crop was smaller. Commercial potato growers cut off all the plants after 3 months this prevents plants from using their energy into growing leaves so plants grow larger potatoes. I have not experimented with cutting plant tops off after 3 month yet but I will this year.

40 years ago my best potato crop was planted in a stack of car tires. There was no internet then it took me 30 years to learn why that worked so well. 7 eyes often grew 30 lbs of potatoes in 2 ft tall stack of tires. I gave plants 5 gallons of water every weekend.
Attachments
100_6706.JPG



Return to “HYDROPONICS FORUM”