Wait for the first Beetom to get stuck under the first platform, then get to the first farm. If the second Beetom is making this farm difficult to use, it may be easier to use the next farm. Jump into the thorns to get invulnerability frames, then run through, luring the Beetoms under the platforms while clearing and using the farms. Note that it is possible to shake a Beetom off of Samus by rapidly turning left and right, or angling up and down, etc. Samus will take 2-4 hits.