SC - Torta of Herbs(Cariadoc's Miscellany) question

[Erin Kenny]

I was looking through the Miscellany at the dessert section and I 
came upon the Torta of Herbs in the Month of May (cites Platina book 
8).

Part of the instructions state: add juice from bleta
Which is defined: 
"Blette-Name given in some parts of France to white beet or chard."
Larousse Gastronomique.]

I was wondering if anyone out there could tell me what relationship 
bleta might have to Swiss Chard.  

I noticed that the redaction used  spinach (with water to produce juice),
and I was thinking that spinach is much more strong tasting than swiss 
chard.  Does this torta end up tasting strongly of spinach?

Just Curious (never had swiss chard till I met my husband, but I like 
it much better than spinach)

Claricia Nyetgale
Canton of Caldrithig
Barony of Skraeling Althing
Ealdormere  (still mostly in the Middle Kingdom)