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Yes, Galium odoratum, aka sweet woodruff, is best grown in containers. In the garden, it quickly spreads beyond its designated space. Another option is to grow it where it is surrounded by concrete as in lawn extensions. It has a strong preference for moist conditions and partial to full shade. https://www.gardeningknowhow.com/edible/herbs/woodruff/growing-sweet-woodruff.htm

The best times to plant perennials are spring and fall after the worst heat of the summer is past. It is very difficult for plants to establish successfully during summer. If you plant this fall, make sure to water all the way into winter so the roots are well-hydrated and more likely to survive. Galium odoratum likes shade and moist soil and is capable of spreading widely, some might say aggressively, where conditions are good. In this respect it is like lily of the valley. However, it is a pretty plant and the floral smell is heavenly.

This can be very difficult. Is this a small area, or throughout the lawn? You can try pulling as many up by hand as possible. The next step will be to make sure that whatever comes up doesn't flower. You will have to keep cutting it to keep it from spreading its seeds. What is underground will be difficult. You can try pouring boiling water on the most aggressive areas. This will kill dense patches without making the soil toxic.

It can certainly help! It will not guarantee that you will not have some escape, but it will help drastically. Digging a spade line kills roots at the tips, where it would spread. It is a way of manual control. This will be the best method, but pairing this will a spade line occasionally will ensure that it stays where it is supposed to.
Sweet Woodruff also spreads by reseeding; so seeds can drop anywhere and start new plants.

Bloom time is late spring to early summer.

Like most plants, when the new green growth comes out, the older, tattered leaves will disappear, but pruning it is okay if you want to have a tidier appearance.

https://www.gardeningknowhow.com/edible/herbs/woodruff/growing-sweet-woodruff.htm

Sweet Woodruff spreads by runners and does best in moist, shady sites. It prefers rich soil kept moist but not soggy.

Keep on the watering, especially during the hot summer days. It also will reseed itself.

https://www.gardeningknowhow.com/edible/herbs/woodruff/growing-sweet-woodruff.htm