i have made my own pumpkin, with seeds and stem but the model for the stem when bent towards pumpkin doesn't work - it shows magenta/black cube.
in code i did everything like vanilla pumpkin so the problem must be with blockstate or model 

Blockstate:
 

{
    "variants": {
        "age=0,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth0" },
        "age=1,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth1" },
        "age=2,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth2" },
        "age=3,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth3" },
        "age=4,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth4" },
        "age=5,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth5" },
        "age=6,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth6" },
        "age=7,facing=up": { "model": "archeology:emerald_pumpkin_stem_growth7" },
        "facing=west": { "model": "archeology:emerald_pumpkin_stem_fruit" },
        "facing=east": { "model": "archeology:emerald_pumpkin_stem_fruit", "y": 180 },
        "facing=north": { "model": "archeology:emerald_pumpkin_stem_fruit", "y": 90 },
        "facing=south": { "model": "archeology:emerald_pumpkin_stem_fruit", "y": 270 }
    }
}

 

model emerald_pumpkin_stem_fruit

{
    "parent": "block/stem_fruit",
    "textures": {
        "stem": "archeology:blocks/emerald_pumpkin_stem_disconnected",
        "upperstem": "archeology:blocks/emerald_pumpkin_stem_connected"
    }
}

why does it not work?

btw i'm getting this model loading error (one of them)
 

[19:29:27] [Client thread/ERROR] [FML]: Exception loading model for variant archeology:emerald_pumpkin_stem#age=4,facing=north for blockstate "archeology:emerald_pumpkin_stem[age=4,facing=north]"
net.minecraftforge.client.model.ModelLoaderRegistry$LoaderException: Exception loading model archeology:emerald_pumpkin_stem#age=4,facing=north with loader VariantLoader.INSTANCE, skipping
	at net.minecraftforge.client.model.ModelLoaderRegistry.getModel(ModelLoaderRegistry.java:153) ~[ModelLoaderRegistry.class:?]
	at net.minecraftforge.client.model.ModelLoader.registerVariant(ModelLoader.java:249) ~[ModelLoader.class:?]
	at net.minecraft.client.renderer.block.model.ModelBakery.loadBlock(ModelBakery.java:153) ~[ModelBakery.class:?]
	at net.minecraftforge.client.model.ModelLoader.loadBlocks(ModelLoader.java:237) ~[ModelLoader.class:?]
	at net.minecraftforge.client.model.ModelLoader.setupModelRegistry(ModelLoader.java:154) ~[ModelLoader.class:?]
	at net.minecraft.client.renderer.block.model.ModelManager.onResourceManagerReload(ModelManager.java:28) [ModelManager.class:?]
	at net.minecraft.client.resources.SimpleReloadableResourceManager.notifyReloadListeners(SimpleReloadableResourceManager.java:132) [SimpleReloadableResourceManager.class:?]
	at net.minecraft.client.resources.SimpleReloadableResourceManager.reloadResources(SimpleReloadableResourceManager.java:113) [SimpleReloadableResourceManager.class:?]
	at net.minecraft.client.Minecraft.refreshResources(Minecraft.java:800) [Minecraft.class:?]
	at net.minecraftforge.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:359) [FMLClientHandler.class:?]
	at net.minecraft.client.Minecraft.init(Minecraft.java:562) [Minecraft.class:?]
	at net.minecraft.client.Minecraft.run(Minecraft.java:387) [Minecraft.class:?]
	at net.minecraft.client.main.Main.main(Main.java:118) [Main.class:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_111]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_111]
	at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
	at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_111]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_111]
	at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
	at GradleStart.main(GradleStart.java:26) [start/:?]
Caused by: net.minecraft.client.renderer.block.model.ModelBlockDefinition$MissingVariantException
	at net.minecraft.client.renderer.block.model.ModelBlockDefinition.getVariant(ModelBlockDefinition.java:78) ~[ModelBlockDefinition.class:?]
	at net.minecraftforge.client.model.ModelLoader$VariantLoader.loadModel(ModelLoader.java:1241) ~[ModelLoader$VariantLoader.class:?]
	at net.minecraftforge.client.model.ModelLoaderRegistry.getModel(ModelLoaderRegistry.java:149) ~[ModelLoaderRegistry.class:?]
	... 24 more

It looks like there should be variants for all ages in the blockstate file, but vanilla pumpkin_stem blockstate doesn't have it and it works without an error

thanks for any help
 

Post model 4 json code please

1 minute ago, diesieben07 said:

There is no such variant in your blockstate json.

It's true that vanilla uses the exact same variants as OP in the blockstates for melon and pumpkin stems, though. Does vanilla allow skipped variants in some way that Forge doesn't?

THANKS