Growing Rice in Raised Beds

This page is my notes for a presentation at the Northeast Grain Growers Association 2012 conference.

Last summer I grew rice in two raised bed paddies. It was fairly simple, as gardening goes, and successful. I ended up with 18 pounds of rice (harvest weight, with stalks) from two 4’ x  8’ by 8” deep beds. I estimate that the actual weight of rice will be about half that.

I got my rice seed from my kind friends Sjon and Elysha Welters, who run Rhapsody Foods in Cabot. The seed is Hayayuki, a short brown rice grown in the far north of Japan. I followed the directions on the packet they gave me:

Soak seeds in early April for 7-10 days. I placed the seeds, husk and all, in the bottom of a small bowl and kept them in about 1/8” of water for a week. Little roots and shoots came out of them, about 3/8” long.

Plant in plugs. At first I used those expanding peat pots. Then I bought some pressed peat starter pots and used some potting soil I had sitting around. When I ran out of the regular potting soil I bought some organic potting soil from Vt. Compost and put it in plastic trays. I would never use expanding peat pots again. The later seedlings caught up with and surpassed the originals. I kept all the seedlings sitting in trays of water to keep them constantly moist.

Harden seedlings off in mid-May for paddy planting in full sun. I never did the hardening bit. I just took them out and planted them with about an inch of sun-warmed water over the dirt.

Plant 2-3 in a hill, 12”x8” rows. I measured out four rows 12” apart across the ends and stretched a string along the length of the bed as a guide. Then I planted 14 rows of pairs of seedlings 8” apart the long way. I just squished the seedling root balls into the mud. I estimate that I planted 206 seedlings total.

Keep plants immersed in water 1”-2” high. Raise water level during growing season from 4” to up to 8”. I never could get more than 4” because of the depth of my beds. It seemed to work.

Notes for the future: I am planning to put strips of poly across the bed in between the rows to minimize evaporation and the resulting cooling. I’d leave the end rows open for frogs.

Harvest in September when 90% of the plants turn brown. I did, with a serrated knife. I brought a roll of baling twine. I grabbed bundles of stalks and cut them off, grabbing and cutting until my left hand was filled. Then I bound the bundle with baling twine.

Note: It is important to keep the root temperature warm and steady, so choose a sunny spot for your paddy. At any time during its growth, raise the water level when you expect colder weather. Pre-heat any water that you will add to the paddy in the sun. I just added water straight from the hose, generally on a sunny morning so it would warm up before sunset. I may add a water barrel to the system this year for preheating.

Each pair of seedlings grew into about 20 stalks, each with one panicle of roughly 30-50 grains. There weren’t always two sets of ten stalks in a pair. Sometimes it was 15 and 5 and sometimes 12 and 8.

I took the bundles inside, parted each one roughly in half, and hung them over a line to dry. This took a few weeks.

I constructed the beds out of rough cut hemlock 2x8. They were simply two four foot ends set inside two eight foot sides, fastened with 4” Timberlock screws, three to a joint.

A friend and I laid out an area for each bed and shoveled the ground flat so each bed would be level. We laid the beds in place and settled them in the dirt.

I cut four pieces of 4 mil clear polyethylene big enough to cover the bottom and go up over the sides and ends with a bit to spare. I put a double layer of poly in each bed and folded the corners like a flat sheet so the plastic didn’t bunch at the corners. I folded a quadruple layer on top of the 2x8 and stapled the plastic all around the edge. Now I had what were essentially two rustic kiddie pools.

I went down to the Vermont Compost Company and loaded my truck with their compost-enriched topsoil, about half a yard, brought it back, and shoveled it into the two beds. It filled them about half way. Then I soaked the soil completely with water until there was half an inch standing on top of the dirt.

Notes for next time:

Kind of level isn’t level enough, and sort of firm soil underneath isn’t firm enough. If the bed is even an inch off over its length then that’s an inch you can’t fill with water.

I should have bought more lumber and built the beds twice as deep. The summer was warm and rainy, so I got lucky. Extra water depth would have given me more security.