If you've grown them before, you know that "usually" the crop grows above the "seed" potato, so you'll have to hill that. curious why you want to start some indoors? Potatos are easy to plant outside, frost doesn't bother them, at least the leaves recover pretty quickly. What we do when I grow potaoes is scratch around the hills and rob small potaos which are usually of edible size with the first green beans. Boil those together with some bacon drippings and YUM, Italian friends do the same thing only use olive oil and call it a soup?

Starting some early is just an experience. No real reason.

How soon do you plant them? When I called a local Farm/Feed store, they claimed that they sold the seed potatoes only in the fall. I wonder if the clerk knew what I was talking about.

How large should the hills be?

Where are you located? In SE Ohio, we try for St. Patrick's day as a target, weather and ho wet the soil is, permitting. Cut potatoes, let cut side dry for a day or so, make a furrow about 6-8 in deep, place potatoes 8-10 in apart, cover, as they grow, pull soil around plant creating hill. Space rows 24-30in. apart. That's a generic description, specific varietals may have subtleties.

Central CT, Zone 5

I plant radishes and peas on St Patty's day.
Is that the same for you? If so, then potatoes for me can go in too.

I think I read that the potatoes will grow above the seed potato. Is that true. I grew a plant or two a long time ago but never noticed the level where the potatoes lived.

This would explain the 6" - 8 " trench and the building of hills as they grow,

Are there any animals that eat them? My raised bed has a metal net below the soil but do I want to secure the fence around the beds? Is it necessary?

St Patty's day may be a bit early in your area, but generally if the ground is workable and not too wet you should be OK. It takes 3 or more weeks for the first leaves to emerge after planting and they can get bit back by a freeze but that usually just slows them down somewhat.

The stolens come out of the stems a couple inches above the seed potato and grow horizontal and the tubers form off of the stolens.

Voles and mice will eat the tubers but your hardware cloth below the bed should protect from that happening. Not much will eat the potato top growth IME but Colorado Potato Beetles can be a problem.

I grew fingerlings years ago and loved them. I ordered some this year, and they will arrive in April. I read that it speeds things up to leave them out for a couple of weeks to let the eyes sprout.

Here, I green sprout the potatoes and plant them about April 14th. I fertilize at planting time...especially with potash.

I'm in NH in the colder side of zone 5. We do have moles, voles and other critters but nothing except Colorado potato beetles have bothered our potato patch. I think they like beets and carrots better. After initial planting, I do my first hilling with dirt but then for the next hilling I used a thick layer of straw. This also keeps down weeds. The trick is to put the straw (not hay) down while the plants are still small so you can get the hay around the stems. The first year I waited too long so there were gaps and I lost some fingerlings that turned green from the sun.

The farm store person must have been new. Garlic is sold and planted in the fall. Potatoes are on display in the spring.

I found the easiest way to keep beetles down is to keep a covered plastic water-filled container handy to the potato patch. I circle the patch and knock any grubs into the container. There's always a few. I wear gloves and squish any eggs but generally it's the pink larvae I see and occasional adult beetles. I don't use any chemical controls.

My potatoes are going strong here in zone 9b. They are in a raised bed, planted deep, and then the soil mounded up around then as they grow. Some people out here grow them in large bags and use straw for mounding. We grew them in the ground as a 4-H project last year and they did fine with minimal mounding.

Small potato experiment

I've never grown them indoors, but usually cut chunks with sprouts and let them dry out for just a few days before planting them outside, and cook/eat the rest :-P I go pretty heavy with it during the cooler months -- we only get a few of those out here in hot/dry SoCal, so better make them count -- and we eat organic, local potatoes from the local CSA so I figure they're no different than seed potatoes that are three times the price. It only took a few times of seeing my shocked, horrified face before my DH learned not to throw anything on the kitchen counter out without asking first, haha! "But honey, they were bits of rotten potato..."

i am not seeking to grow them indoors rather get them started early. Maybe it is fruitless (NPI) as I figured I would just give it a try.

Do the new ones grow above, to the side of, or below, the seed potato?
I do know that it is below the greenery.

Never hurts to try! If it's too cold to get them growing outside, it could be an interesting experiment to start them indoors. The only downside I could see is if moving them somehow damaged their root system, or the change in climate shocked them. But you'll never know until you try, and I'm sure a lot of people would be really interested in your experiment findings. :-)

I'm no expert, but I've found that my potatoes are usually in clusters not too far from the original seed potato or potato chunk. To the side of and slightly above it, I would say. Maybe it is different depending on the potato type, or I am just not doing it right ;-) but I have never experienced potatoes growing higher than a foot or two from the seed. IME the only benefit I really got from generous hilling was that none of the potatoes turned green from light exposure. There may be other more experienced potato growers here with different experience...

Here is a thread you might find interesting: http://forums2.gardenweb.com/discussions/1485284/is-there-such-a-thing-as-indeterminate-and-determinate-potato-var?n=13

I enjoyed the link. It approaches TMI !!
Why can't these things ever be simple...?

Potatoes ARE simple. Dead simple. That doesn't mean some folks won't get in the zone with them. They're almost plant-and-forget food, perfect for a little experimentation. I hear you can grow them on Mars...

Just get a couple or four varieties and plant them in a shallow trench. Plant half when you think it's a good time, plant the other half two weeks later. Keep the sunlight off the tubers as they grow, some with dirt and some with huge amounts of mulch. Ignore fertilizer. Ignore pH. Ignore the "certified $eed potato" labels. Avoid really old heirlooms your first year. See what works best for you and your area. That's it!

Yes, I do see them as "plant and forget" but I run into Early Middle and late season however the date to maturity is scarcely 10 days apart...

I see tubers that grow up the stalk hence, therefore ergo, they need a pile of mulch. I see tubers that grow at a given level... I have Organic Russian Banana Fingerling, Yukon Gold, and Elba and not have to look into their behaviors.

Thanks for the tip of growing a set two weeks later. Yes, I forget all about fertilizers and Ph although I know the ph is low but not quite low enough for blueberries.

My earlier experience was to just plug one into the ground and it grew and produced a nice harvest,

I should stop reading about them as I get a multitude of opinions and suggestions. Of course, everyone has at least one of each.

I will experiment with a starter set some time soon to transplant when the soil is warm. Setting them in pots will help the transplant as I know that they won't like the change. I have been successful with other plants of which I have been told to never do and they will never survive.. (:

Moose's Tubers website has good information about most any Potato type available. Most all fingerlings are in the late category, Yukon Gold is early and a pretty good keeper and Elba is late and is supposed to be a very good storage potato. I group my potatoes by maturity time in my beds. I will be growing LaRatte fingerling and Red Pontiac which are both late in the same bed. My early Yukon gold will have it's own bed. I am also thinking about growing either Burbank Russet or German Butterball if I can find some seed locally.

Moose's Tubers