F1 resumes from its summer break with this weekend's Belgian Grand Prix at Spa-Francorchamps, which is followed up a week later by the Italian Grand Prix at Monza.
The Renault factory team is currently sixth in the constructors' championship with 39 points, 43 less than engine customer McLaren, and neither Hulkenberg nor team-mate Daniel Ricciardo have scored points in the last two races.
“The break certainly came at a welcome time for us after a disappointing July,” said Hulkenberg.
“We know the season has fallen below our expectations so far and it's up to us now to ensure we recover it for the remainder of the year.
“I relaxed a little, recharged the batteries on a boat in Croatia. But now it's time to get going again and I'm ready for the challenge.
“These next two back-to-back races are almost a make or break for our season. We have to be on it.”
Tripping up with Sergio Perez during qualifying at the following round in Hungary, just before the break, also ruined the West Australian's weekend in Hungaroring.
Ricciardo said on the eve of that round that there would not be upgrades to the R.S.19 chassis until “the first few” races after the summer break, and believes that “cleaner weekends” are key in the upcoming events.
“It's been a challenging season so far, we can't hide from that,” he conceded.
“There have been some positives, some things not so good, so the summer break was ideal for us.
“It was nice to take some time off, have a holiday in Los Angeles, and not think too much about racing. It was the same for the team, so hopefully we're all feeling refreshed now.
“We're targeting a better second-half of the season to catch our competitors. I know we can do it, we just need cleaner weekends.”
Practice at Spa-Francorchamps starts on Friday at 1900 AEST.