Steve Crane worked all day Tuesday planting potatoes in the fields of Exeter, directing the process from the cab of a state-of-the-art GPS outfitted tractor.

He carefully watched six computer screens, using technology to determine his planting to the inch. Once the geographical data are programmed into the on-board computer, the computer guides the tractor’s direction across the fields. Crane really has to control only its speed.

But all the technology in the world can’t control Mother Nature.

Crane may have planted Tuesday, but on Wednesday and Thursday, rain forced him into the barn. Friday was unexpectedly sunny and he was able to return to the fields.

“We were held up a bit by bad weather and got a slower start than usual, but if there hadn’t been that rain, we could have caught up,” Crane said. Crane Bros. operates two potato farms — one in Exeter and another in Canton — and each spring plants 1,300 acres.

“We like the soil temperature to be 45 to 50 degrees,” Crane said, laughing because Maine’s soil temperatures have not reached there yet. “But let’s face it, it’s not going to get colder between now and the end of May.” Crane said he needs 15 to 18 good days to get the planting done and this week’s rain is holding everything up.

It was appropriate, then, when the spring farmers’ outlook report to the U.S. Department of Agriculture for New England released this week was titled “It’s Wet Out There.”

The report, generated by the New England Agricultural Statistics Service, a division of USDA, compiles early spring information from farmers, cooperative extension agents and others in the agricultural industry. The report said that last week only three days were available for field work across New England. Pasture condition was rated good to fair, yet this week brought frequent precipitation.

Although there was snow still present in some Aroostook County fields, southern Maine wasn’t much further ahead.

“This spring is quite a bit different than last year. It’s been a long slow spring and perennial crops are a bit behind,” Sandy Truslow of the Farm Service Agency in Cumberland and York counties reported. “Farmers are tilling fields and spreading manure. The only plantings I’ve seen are under plastic. The grass has just greened up and is not quite tall enough for pasturing.”

Janet King of the Farm Service Agency in Somerset County said producers are reporting that conditions are about two weeks behind last year, due to the late spring snowstorms.

“The grass is just now starting to green up, and most fields are too wet and soft to spread manure due to snow melt,” she said. “Field work is minimal at this time, yet some manure spreading on the high and dry areas has been done. There were reports of snow and hail storms in some areas on April 20, and flooding was a concern during the last week of April due to snow melt and runoff with spring rains.’’

The assessment is that temperatures have overall been cooler than normal, and warm May weather is needed to get the grass and crops growing.

“But we are far better off than some of the other New England states,” grass and hay expert Rick Kersbergen of the Waldo County Extension office said this week. “Other places have had 10 inches of rain in the last two weeks, and Aroostook County is still plenty wet.”

Kersbergen said some farmers are getting frustrated because their fields are too wet to plant. “But the grass is green and growing. Maine grows cool-weather grasses and they like it like this.”

The NASS report indicates that all fruit crops — apples, peaches, pears, strawberries and cranberries — were reported to be in good to fair condition across New England with the exception of wild blueberries, which were assessed at good to excellent development.

In Maine, multiple mummy berry infections — a blight that can strike blueberry plants — have occurred in Lincoln, Knox, Waldo and Hancock counties, and farmers are working to contain those.

Where they can get into their fields, vegetable growers are plowing, disking and spreading lime. They are planting peas, sweet corn, lettuce and greens.

In central Maine, David Handley said the conditions were about as close to normal as Maine farmers have seen in a long time. Handley is the fruit and vegetable expert at the University of Maine’s Highmoor Research Farm.

“Where the soil is well drained, farmers are getting in their peas and corn,” he said. He contrasted this spring with last year, noting that 2010 saw a very early spring which was complicated by a heavy late frost in May that damaged fruit trees and planted crops. “I’d say that this week we have some pretty good growing conditions,” he said.

“Maine’s fruits and vegetables have sort of a coiled spring nature, and when we get a few days of warmth, they really pop,” he said.

Larry James of the Farm Service Agency reported that in central Aroostook County a few farms are breaking ground, but there is still some snow in the woods and along fence lines. Pam Hickey of the extension office in central Aroostook said grains may be planted by next week if fields dry out and snow melts.

“We had one of the best seasons for maple syrup production in recent years,” Gary Raymond of FSA in Franklin County said. “The snow just finished melting last week. There is still some in the mountains. Because the frost is just coming out of the ground, field work began in earnest at the end of last week.”

Valerie Porter of the Farm Service Agency for Hancock, Penobscot and Piscataquis counties had a similar assessment.

“Wet ground has kept most farmers waiting to get their spreading done,” she said. “Rainy days ahead will keep things at a standstill again. Farmers really need a good week of dry weather to be able to get going on plantings and ground preparation.

Dr. David Yarborough, the extension’s wild-blueberry expert, said that in Washington County wet conditions and a late spring snowstorm have delayed pruning in many fields. Some fields are being pruned by mowing and burning.

“But really,” Handley assessed. “All we can do is cross our fingers.”