40d:Farming

General farming flowchart.

Farming is the most universal source of food in Dwarf Fortress. On maps with plentiful shrubs, animals or bodies of water, plant gathering, hunting or fishing can also produce a lot of food; however, these practices often do not scale to the level needed to feed a full-sized fortress. Farming is a highly efficient, reliable, renewable and scalable source of food -- and, after cooking, of compact but valuable trade goods. Plants are also the only source of alcohol and dye other than trading. Some can be turned into clothing.

Finding farmland

You cannot plant seeds on a bare rock floor, only on mud or soil. The easiest way to farm, by far, is to find some soft, arable soil, which is available in great quantity outside the fortress on most maps (the notable exceptions being mountainous maps). If arable soil is unavailable, you will need to set up an irrigation scheme to deposit mud on the bare rock, which can then have farm plots placed upon it.

Aboveground or underground?

You can plant either underground or aboveground, depending on the type of plants you want to grow. The starting seeds your dwarves may bring with them can only be planted underground. If you want to farm aboveground, you will need to gather seeds from outdoor shrubs, which can then be planted. Caravans will also sometimes bring additional bags of seeds.

The farm plot should be either entirely above ground or entirely subterranean. A mixed-class farm plot will allow you to choose any crop for planting, but the chosen crop will be planted only on tiles capable of growing it. Worse, planters will not skip over the infertile tiles, leaving the rest of the plot fallow whether it can support the crop or not.

Greenhouses

If you want a secure way to farm outdoor plants indoors build a greenhouse!
Channel out a square area, you can also use the remains of a dried up pond.
Now build floors out of Glass blocks, this will allow light to pass through, but not invaders. This can in fact be done with any kind of floor, including raw stone, since the area beneath the floor will still receive light and while still being indoors. This may be an exploit.
You can now Plant above ground plants like strawberries or Long Land grass in the light, underground.
CAUTION, You must channel out the area first then make the floor, it won't work if you make the block floor and mine underneath.

Defining the farm plot

Once you have a suitable location for farming you can have your farmer(s) prepare a farm plot. That's the actual bit of soil to be tilled.

Enter the build menu and place farm plots. Use u and k to increase the size of the plot, and m and h to decrease it. When the plot is sized and positioned correctly, pressing Enter will place it. Your grower(s) will now rush in and prepare the field, clearing out rubble and other impediments when necessary.

How much farm space do you need? Surprisingly little. A 5x5 plot will provide enough food to bring you through your first winter, and even smaller fields are sufficient if you stretch out the food by brewing. If there is rubble in the room, leave a little extra space; otherwise, the farmers tend to stack the boulders under your farm room doors and cause them to get stuck ajar, which if you're not careful can lead to flooding the next time the field is irrigated. You can also avoid putting doors right next to the farm.

Digging out larger farm rooms than you need can be useful in other ways as well: muddied areas can spontaneously produce tower-caps (a source of wood), spider webs (a source of silk), and shrubs of the same type as your crops.

A 10x20 plot should, with several dedicated farmers, provide enough food to feed a full 200-dwarf fortress.

Planting

Once a farmer builds the plots, it's time to plant. Go into the plot's q menu and select the type of seed to plant. Your farmers will then take care of the rest. Note that your farmers will not work the plot the whole year without being told to do so: you must designate a crop for each season. You can designate each season ahead of time by using a, b, c, d from the plot selection screen. You cannot designate crops for seasons already past; you will need to remember to do this in the following spring. You do not have to plant the same thing each season, and some plants are only available during certain seasons.

On a farm that is built but not planted, each tile will look like a solid (not blinking) double tilde (~). Once a square has been planted, it will look like a double line. Once the square has been harvested, it will return to the previous state (double tilde).

In the first year, you may want to focus your production on berries aboveground, or fast growing plump helmets underground, because they can be brewed and eaten raw or cooked. Quarry bushes, cave wheat and sweet pods require processing before they can be eaten and take longer to grow. Pig tails and dimple cups can produce cloth and dye respectively, so grow these later. Dimple cups are the only underground crop that can neither be brewed nor otherwise processed into food (except for its seed, which can be cooked). Consider processing and cooking (and adjusted farming) as soon as possible since it adds quality levels to your food and in the case of quarry bushes and sweet pods quintuples the amount of food. Also, if you want to cater for the preferences of your dwarves, you will likely grow all types of crops sooner or later.

You cannot buy berry seeds upon embarking. If you choose to plant berry shrubs, designate a dwarf with herbalism to gather plants outside until you get some suitable plants, then brew them to get the seeds. You may also trade for outdoor seeds directly from a non-dwarven caravan, which can be a very effective way of getting a lot very quickly. Make sure the outside farm plot is designated in the same biome that the plants were gathered from.

Should you wish to plant nothing for a season, you can select z "fallow" from the farm plot menu; this is useful when your larder is overful. If you possess potash, you can fertilize the field to increase yield (see below).

Increasing yield

Any crop may bear more or less fruit, or (as is sometimes the case with unskilled growers) it may even bear no fruit at all, thus wasting the seed. A higher yield will have many benefits along the whole assembly line of further food processing: workers will always work one one "stack" at a time – if (for example) a brewer has "sweet pod [5]" to work with, he will produce "dwarven rum [25]" and somehow squeeze it all into a single barrel.

The yield from a single seed depends on the farmers' skill and, if above ground, on whether the plot was fertilized.

skill: no particular skill is checked when harvesting. Only the grower skill of the farmer who planted the seed is taken into account. Dabbling planters will frequently produce stacks of only one, and sometimes even zero plants. Legendary growers will often produce "plant name [5]" and rarely even "plant name [6]" stacks from a single seed on a non fertilized field.

fertilization: above ground fertilization increases yield up to about 1.5 times^[Verify]. It is currently not possible to fertilize underground plots. The amount of potash needed to fully fertilize a field depends on its size. Using q to view the farm plot, look for the field that looks like "n/N ft." n is the amount of fertilizer applied so far, while N is the maximum amount that may be applied. To fertilize the field choose the fertilize command. The seas Fert option tells your dwarves to automatically fertilize a field after each season change.

In a discussion concerning the chances to get stacks of 6 plants, Toady has mentioned:

Yeah, even a novice farmer will get 6 of them once out of every 12000000 attempts. 
I think the most you can get is 11 with full fertilization and good farming skill rolls (and some luck).

Harvesting

A few weeks after planting a seed, a crop will sprout on that spot. Crops must be harvested within another few weeks or they will wither. By default, all dwarves will harvest, including children and even nobles. This may or may not be desirable: on the one hand, it makes sure that no crops will wither; on the other, it may lead to far away dwarves interrupting their work and running a long way in order to harvest a single plant and less skill gains for your planters.

Harvesting plants earns dwarves experience in the "growing" skill, so do not be surprised if all your dwarves soon become "dabbling" (or better) growers. Because of that, peasants with no other occupation become farmers almost automatically. Do not be afraid that they might trample your fields: the skill is of no importance during harvest, and no matter how much skill they earn they will still only plant crops if you allow them to in their individual "labor" menu.

If you chose to turn off "All dwarves harvest" in your orders menu, only dwarves with the "Farming (Fields)" labor enabled will harvest. However, they will often choose to plant new seeds instead of reaping the existing crop, so you risk that some amount may wither. After harvesting a plant (plucking it out of the ground), dwarves will carry it to the nearest stockpile unless you have "Dwarves ignore food" set in your orders menu, in which case they will leave the plant blinking on the field. If not moved to a stockpile within a few weeks, it will wither.

Caveats (warnings)

Food hauling

If you manage to get large-scale farming up and running, you will need to employ many food haulers in order for the food produced on your farms to be edible, even if it has already been harvested. This is because in the current version of the game, items tagged for pending tasks (including Move to Stockpile and Store in Barrel) are unavailable for any other use -- such as eating. An entire fortress of dwarves can starve while they wait for somebody to move the food.

One way to deal with this problem (at least during the heavy farming/harvesting seasons) is to disable hauling of both stone and wood in the top-level orders menu. This way, most of those jobs will clear out of the job queue, and you will be left mostly with "Store in Barrel" type jobs. You can also increase the number of dedicated food haulers.

Storage

It can be difficult to manage barrels to store food and drink, and bags to store seeds and processed foods. Combat this by cooking food to consolidate it into larger stacks that won't rot outside of a barrel (it just needs to be indoors on a food stockpile). In the p menu, you can also reserve some empty barrels that will not be used for food storage; instead, they will only be used for brewing and syrup processing tasks. Leaves, sugar, and flour are not edible; to use them up and free their bags, you must cook. You can also cook excess seeds (albeit only up to 4 at a time), to reclaim the bags they occupy. Make sure not to cook your last crop seed!