Plant roots don’t need gravity to draw water! Plants use evaporation and the tensile strength of water (yes, really!) to draw water up against gravity.
While that is true, plant roots and stems use gravity to know in which direction to grow (roots down and stems up), so that will cause problems in space.
NASA has succeeded to grow some plants on the ISS, by making them grow towards a source of light (i.e. LEDs), but until now this has worked only for some very low-growing plants, like lettuce and some varieties of cabbage, not for plants with deep roots and high stems.
It should be much easier to grow algae in the absence of gravity, but those are not as tasty as terrestrial plants.
It's very odd to phrase it as "tensile strength", but capillary action is an expression of surface tension, which is the result of molecular cohesion--two (water) molecules resisting separation. In other words, strength under tension, with measurable stress and strain. With some squinting, you've got tensile strength with elastic deformation.
I think you are right and that is what they are getting at, but it is more a property of the system, not thee material. It is hard to reconcile fluid flow of a liquid with tensile strength.
NASA has succeeded to grow some plants on the ISS, by making them grow towards a source of light (i.e. LEDs), but until now this has worked only for some very low-growing plants, like lettuce and some varieties of cabbage, not for plants with deep roots and high stems.
It should be much easier to grow algae in the absence of gravity, but those are not as tasty as terrestrial plants.