Can you use a Glyph of Warding and Plant Growth to set up a semi-permanent effect in an area?
Background
I am a Cleric/Druid in one of the campaigns I play in and the setting is an area with very little vegetation, bar some oases. Even then, the plants here have been suffering. So, I want to help the small settlements that are dotted about the area by using the permanent effect of Plant Growth.
This got me thinking about using the spell in conjunction with Glyph of Warding, to create a semi-permanent effect to really help these areas flourish and help the local villages in this region.
I want to cast Glyph of Warding in conjunction with the eight-hour version of Plant Growth, where I set a trigger of time, e.g. that one, or two, or three years have elapsed, and so forth. Would it be possible to set them up so that they trigger over a sequence of many years? Ideally, I want to be able to enrich the land of an area for 100 years. I could get other spell-casters to join me with this.
Is it possible to use Glyph of Warding and Plant Growth to set this up?
Thanks for your help with this.
Plant Growth
If you cast this spell over 8 hours, you enrich the land. All plants in a half-mile radius centered on a point within range become enriched for 1 year. The plants yield twice the normal amount of food when harvested.
(PHB p.266)
and
Glyph of Warding
Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph by casting it as part o f creating the glyph. The spell must target a single creature or an area. The spell being stored has no immediate effect when cast in this way. When the glyph is triggered, the stored spell is cast. If the spell has a target, it targets the creature that triggered the glyph. If the spell affects an area, the area is centered on that creature. If the spell summons hostile creatures or creates harmful objects or traps, they appear as close as possible to the intruder and attack it. If the spell requires concentration, it lasts until the end o f its full duration.
(PHB pp. 245-246)