A center trainee controller reported they waited too long to climb an aircraft to a higher altitude ...

Narrative:

I received a handoff on aircraft X. I immediately recognized the aircraft was too low for my terrain. I pulled up my mia (minimum IFR altitude) map; ran a route line; and verified the aircraft would need to be at 14;000 ft. To be above mia. When aircraft X checked on; I immediately asked the aircraft if they were capable of 14;000 ft.; or if they would prefer a vector to south to stay in lower mia. The pilot of aircraft X responded 'yeah; 14;000 ft. Is no problem!'. I told the aircraft to expect higher in 10 minutes; and the pilot of aircraft X read back 'expecting 14;000 ft. In 10 minutes.' I had made the decision to climb the aircraft near a VOR which was about 3 to 4 minutes flying time from the higher mia. I checked the aircraft climbing characteristics on erids; which showed the aircraft was capable of 900 ft. Per minute. As the aircraft would only need to climb 1;000 ft.; I felt comfortable giving the climb later which was roughly 10 minutes from his current position.I gave the instruction to climb to 14;000 ft. The pilot of aircraft X read it back correctly. The plane did not climb immediately. It took much longer than I expected for the aircraft to begin climbing; especially given that the pilot was expecting a climb. Once the aircraft began climbing; I noticed the aircraft was only doing about 100 ft. Per update. The aircraft went a few updates without climbing at all. At this point; the aircraft was within the 13;900 ft. Terrain bubble. Knowing that the peak in that terrain bubble is near the center; I decided that as a safety measure I would turn the aircraft away from the center as he continued his climb. I gave the aircraft 10 degrees right; which the pilot followed. Once the aircraft showed level at 14;000 ft. And MSAW (minimum safe altitude warning) alert was done; I cleared the aircraft back on his route.I could have provided the pilot with an earlier climb. I held off giving the pilot an early climb due to the confidence in his answers. I didn't think climbing to 14;000 ft. Would take as long as it did. If I gave a clearance to climb earlier; the issue wouldn't have occurred. The aircraft was on the south edge of a 13;900 ft. Terrain bubble. If I would've given the aircraft present heading sooner or a 5 degree right turn; I could've avoided the 13;900 ft. Bubble all together.

Original NASA ASRS Text

Title: A Center trainee controller reported they waited too long to climb an aircraft to a higher altitude to stay above the Minimum IFR Altitude for its route.

Narrative: I received a handoff on Aircraft X. I immediately recognized the aircraft was too low for my terrain. I pulled up my MIA (Minimum IFR Altitude) map; ran a route line; and verified the aircraft would need to be at 14;000 ft. to be above MIA. When Aircraft X checked on; I immediately asked the aircraft if they were capable of 14;000 ft.; or if they would prefer a vector to south to stay in lower MIA. The pilot of Aircraft X responded 'Yeah; 14;000 ft. is no problem!'. I told the aircraft to expect higher in 10 minutes; and the pilot of Aircraft X read back 'expecting 14;000 ft. in 10 minutes.' I had made the decision to climb the aircraft near a VOR which was about 3 to 4 minutes flying time from the higher MIA. I checked the aircraft climbing characteristics on ERIDS; which showed the aircraft was capable of 900 ft. per minute. As the aircraft would only need to climb 1;000 ft.; I felt comfortable giving the climb later which was roughly 10 minutes from his current position.I gave the instruction to climb to 14;000 ft. The pilot of Aircraft X read it back correctly. The plane did not climb immediately. It took much longer than I expected for the aircraft to begin climbing; especially given that the pilot was expecting a climb. Once the aircraft began climbing; I noticed the aircraft was only doing about 100 ft. per update. The aircraft went a few updates without climbing at all. At this point; the aircraft was within the 13;900 ft. terrain bubble. Knowing that the peak in that terrain bubble is near the center; I decided that as a safety measure I would turn the aircraft away from the center as he continued his climb. I gave the aircraft 10 degrees right; which the pilot followed. Once the aircraft showed level at 14;000 ft. and MSAW (Minimum Safe Altitude Warning) alert was done; I cleared the aircraft back on his route.I could have provided the pilot with an earlier climb. I held off giving the pilot an early climb due to the confidence in his answers. I didn't think climbing to 14;000 ft. would take as long as it did. If I gave a clearance to climb earlier; the issue wouldn't have occurred. The aircraft was on the south edge of a 13;900 ft. terrain bubble. If I would've given the aircraft present heading sooner or a 5 degree right turn; I could've avoided the 13;900 ft. bubble all together.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1741390
Time
Date	202005
Local Time Of Day	1801-2400
Place
Locale Reference	ZLC.ARTCC
State Reference	UT
Aircraft 1
Make Model Name	PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	Climb
Route In Use	Direct
Flight Plan	IFR
Person 1
Function	Enroute
Qualification	Air Traffic Control Developmental
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy Deviation - Procedural Clearance Inflight Event / Encounter CFTT / CFIT

A center trainee controller reported they waited too long to climb an aircraft to a higher altitude to stay above the minimum IFR altitude for its route.