Potatoes need lots and lots of water to produce good crops, also, If they are an "early" variety then they won't produce large tubers and take 13 to 15 weeks to mature. "Main crop" varieties take around 17 weeks to mature.

At 18 inches and just flowering now tells me they are not quite ready yet!
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Pommes de terre ont besoin de beaucoup et beaucoup d'eau pour produire de bonnes récoltes, aussi, si elles constituent un "début" variété, puis ils ne seront pas produire de gros tubercules et de prendre 13 à 15 semaines pour mûrir. «Récolte principale" variétés de prendre environ 17 semaines pour mûrir.

À 18 pouces et un peu la floraison maintenant me dit qu'ils ne sont pas encore tout à fait prêt!

Just showing off, but the translation for 'early' in 'early potatoes' would be 'precoce', not 'debut', and 'late' would be 'tardive'. In the same way second earlies are demi-precoce and 'demi tardive' for mid season.

And I'm appalled you didn't change the 'pouces' into 'centimetres'.
LOL!

Oops, sorry Birtie but it wasn't a bad effort for my schoolboy French? Which was a looooong time ago! Lol

google translate is great! lol

Shhhh Heidib, you'll give the game away!

Google translate obviously isn't in to horticulture like the rest of us. But it always amazes me how good a translation it gives even for technical subjects.

I did do the original myself but used G. translate to verify my schoolboy attempt!
I wish I had studied harder now! Lol