Oesten's 'Among the Roses' is a charming salon waltz, characteristic of the Romantic era, that aims to evoke a sense of pleasant sentimentality and grace. Its appeal lies in its tuneful melody and smoothly flowing accompaniment.
Cultivating a graceful legato and precise waltz rhythm is key.
Among the Roses (Op.318) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Among the Roses (Op.318) lasts about 3.5 minutes.
Among the Roses (Op.318) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.