JavaFX: How to make a VBox and it's contents expand infinitely with window height like they do with

Probably a very simple question but I have not been able to figure it out.

I have a ScrollPane (feat. Label) inside a VBox, inside a SplitPane:

(Full fxml file at the bottom)

When you expand the window or the split pane seperator horizontally, the Vbox automatically stretches to fit, the label re-centers appropriatelly, and the scroll pane expands to fit the vbox. This does not happen when epxanding vertically, and I would like it to. How can I achieve that? If there is a different container I should be using instead, please do tell.

Gif of my troubles if it helps: Full fxml file:

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.text.*?>

<AnchorPane prefHeight="600.0" prefWidth="800.0" xmlns="http://javafx.com/javafx/10.0.2-internal" xmlns:fx="http://javafx.com/fxml/1" fx:controller="main.java.ui.DefaultLayoutController">
   <children>
      <BorderPane prefHeight="600.0" prefWidth="800.0" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
         <top>
            <MenuBar BorderPane.alignment="CENTER">
              <menus>
                <Menu mnemonicParsing="false" text="File">
                  <items>
                    <MenuItem mnemonicParsing="false" text="Close" />
                  </items>
                </Menu>
                <Menu mnemonicParsing="false" text="Edit">
                  <items>
                    <MenuItem mnemonicParsing="false" text="Delete" />
                  </items>
                </Menu>
                <Menu mnemonicParsing="false" text="Help">
                  <items>
                    <MenuItem mnemonicParsing="false" text="About" />
                  </items>
                </Menu>
              </menus>
            </MenuBar>
         </top>
         <center>
            <SplitPane dividerPositions="0.5" prefHeight="160.0" prefWidth="200.0" BorderPane.alignment="CENTER">
              <items>
                <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
                     <children>
                        <VBox prefHeight="573.0" prefWidth="306.0" style="-fx-background-color: #ccbfb1;" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
                           <children>
                              <Label alignment="CENTER" maxWidth="Infinity" prefHeight="61.0" prefWidth="260.0" style="-fx-alignment: center; -fx-background-color: #e6d7c8;" text="Text" textAlignment="CENTER">
                                 <font>
                                    <Font name="AdobeDevanagari-Regular" size="51.0" />
                                 </font>
                              </Label>
                              <ScrollPane fx:id="mainScrollPane" prefHeight="559.0" prefWidth="453.0">
                                <content>
                                  <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="200.0" prefWidth="200.0" />
                                </content>
                              </ScrollPane>
                           </children>
                        </VBox>
                     </children>
                  </AnchorPane>
                <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="573.0" prefWidth="364.0">
                     <children>
                        <VBox prefHeight="573.0" prefWidth="396.0" style="-fx-background-color: #e6c896;" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0" />
                     </children>
                  </AnchorPane>
              </items>
            </SplitPane>
         </center></BorderPane>
   </children>
</AnchorPane>