IOWA CITY | There was a time when the corn crop was considered to be in good shape if it were knee high by the Fourth of July.

Times have changed for other commodities as well.

Iowa is well on its way to harvesting a bumper crop of football recruits.

Expecting to have around 20 scholarships to offer in its 2013 recruiting class, Hawkeye coaches have already secured 15 verbal commitments from incoming high school seniors.

In his first 13 seasons as Iowa’s head coach, Kirk Ferentz had never collected more than seven verbal commitments before July 1 and a year ago, the Hawkeyes only had five players who had announced their intentions to sign with Iowa by that date.

Although recruits cannot sign binding letters of intent until Feb. 6, nine Big Ten schools already have at least 10 commitments for their 2013 recruiting classes.

Ferentz saw signs that the recruiting process was speeding up nationally in the spring, when a larger number of high school juniors made spring break visits to the Iowa campus.

Many took advantage of the opportunity to watch spring drills during those visits which have ultimately led to quicker commitments.

“We really haven’t changed that much in the way we go about things,’’ Ferentz said. “We’ve maybe been a little more aggressive, but not dramatically. Things are moving faster. I think what we’re seeing is really more of a reflection of what is going on nationally.’’

Iowa picked up six of its commitments within a span of 72 hours during the final weekend of June, a group that will likely represent more than a quarter of the Hawkeyes’ entire recruiting class.

NCAA rules prohibit Ferentz from speaking about the individuals who have committed to Iowa until they sign letters of intent, but the Iowa coach said he is pleased with the overall success the Hawkeyes have had.

“We’re really excited about the way things have been going, the group that has committed,’’ he said. “But, it is a long race to run.’’

That marathon continues.

In addition to looking for the right players to fill remaining available scholarships, Ferentz said that Iowa must continue to recruit the players who have already made verbal commitments.

“You have to continue to recruit those guys. Verbal commitments are just what they are, verbal commitments,’’ Ferentz said.

“You have to keep recruiting them. It seems like most people who have declared here over the years are pretty good about honoring their commitment, but it’s not uncommon to have a surprise. We’ll continue to recruit them as hard as we would if they had not committed at this point.’’