Mog Garden: Have rank 6 key item but garden furrow still rank 5

[Pheonixistari]

Platform: Windows
ISP: Cox Communications
Type of Internet Connection: Cable
Internet Connection Speed: 50Mbps
Date & Time: Feb. 8, 2015 13:45 MST
Frequency: Once (can not reproduce due to nature of key items)
Character Name: Pheonixistari
Race: HumeM
World: Phoenix
Main Job: Thief, Lv.99
Support Job: Dancer
Area and Coordinates: Mog Garden
Party or Solo: Solo
NPC Name: Garden Furrow
Monster Name: n/a
Steps:
I bought the key item "Arboreal Abracadabra" for 80,000 gil for rank 5 furrows in the Mog garden from the skipper moogle in port windurst. Upon going back into my garden i noticed i did not have 3 furrow rows. I thought maybe the wikipedia article on mog gardens was wrong and continued to use the garden as normal. Upon using the furrows enough to purchase the rank 6 key item i went to the skipper moogle in port windurst and bought the key item "Verdant and Verdon'ts" for 80,000 gil for rank 6 furrows in the mog garden. I thought the price change was strange for buying a rank 6 key item. After returning to my mog garden i noticed i do now have 3 rows of furrows but the game also tells me that my furrow is only rank 5 even though i posses the permanent key item "Verdant and Verdon'ts".

EDIT: It says I can't post a reply so I have to edit in a response here. It seems Love Mango is correct and that I got confused with the Furrows and the Grove. Please close this topic and no need to investigate further as this is not a bug more my own confusion.

[LoveMango]

Checking the descriptions of the KIs you mentioned, they both appear to be for ranking up the grove (logging/harvesting) rather than the furrows. You can check what each KI does yourself in Permanent Key Items and see how many you actually have for the furrows. Things like "Fields And Fertilizing", "Designer Farming", "Homesteader's Compendium", and "MHMU Treatise on Agronomy".