diff --git a/README.md b/README.md
index 5597445..fe2f249 100644
--- a/README.md
+++ b/README.md
@@ -150,12 +150,13 @@ that required paid sponsorship upon exceeding a free limit.
 
 ### `prepare` stage
 
-| Argument        | Default     | Description                                                                          |
-|-----------------|-------------|--------------------------------------------------------------------------------------|
-| `--concurrency` | 1           | Maximum number of concurrently running Tart VMs to calculate the `auto` resources    |
-| `--cpu`         | no override | Override default image CPU configuration (number of CPUs or `auto`<sup>1</sup>)      |
-| `--memory`      | no override | Override default image memory configuration (size in megabytes or `auto`<sup>1</sup>) |
-| `--dir`         |             | `--dir` arguments to pass to `tart run`, can be specified multiple times             |
+| Argument         | Default     | Description                                                                                                                                                     |
+|------------------|-------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `--concurrency`  | 1           | Maximum number of concurrently running Tart VMs to calculate the `auto` resources                                                                               |
+| `--cpu`          | no override | Override default image CPU configuration (number of CPUs or `auto`<sup>1</sup>)                                                                                 |
+| `--memory`       | no override | Override default image memory configuration (size in megabytes or `auto`<sup>1</sup>)                                                                           |
+| `--dir`          |             | `--dir` arguments to pass to `tart run`, can be specified multiple times                                                                                        |
+| `--auto-prune`   | true        | Whether to enable or disable the Tart's auto-pruning mechanism (sets the `TART_NO_AUTO_PRUNE` environment variable for Tart command invocations under the hood) |
 
 <sup>1</sup>: automatically distributes all host resources according to the concurrency level (for example, VM gets all of the host CPU and RAM assigned when `--concurrency` is 1, and half of that when `--concurrency` is 2)
 
diff --git a/internal/commands/prepare/prepare.go b/internal/commands/prepare/prepare.go
index 537cec6..5769266 100644
--- a/internal/commands/prepare/prepare.go
+++ b/internal/commands/prepare/prepare.go
@@ -24,6 +24,7 @@ var concurrency uint64
 var cpuOverrideRaw string
 var memoryOverrideRaw string
 var customDirectoryMounts []string
+var autoPrune bool
 
 func NewCommand() *cobra.Command {
 	command := &cobra.Command{
@@ -40,6 +41,9 @@ func NewCommand() *cobra.Command {
 		"Override default image memory configuration (size in megabytes or \"auto\")")
 	command.PersistentFlags().StringArrayVar(&customDirectoryMounts, "dir", []string{},
 		"\"--dir\" arguments to pass to \"tart run\", can be specified multiple times")
+	command.PersistentFlags().BoolVar(&autoPrune, "auto-prune", true,
+		"Whether to enable or disable the Tart's auto-pruning mechanism (sets the "+
+			"TART_NO_AUTO_PRUNE environment variable for Tart command invocations under the hood)")
 
 	return command
 }
@@ -55,6 +59,14 @@ func runPrepareVM(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
+	// Auto-prune is enabled by default in Tart,
+	// so we only need to act when it's set to "false"
+	if !autoPrune {
+		if err := os.Setenv("TART_NO_AUTO_PRUNE", "true"); err != nil {
+			return err
+		}
+	}
+
 	gitLabEnv, err := gitlab.InitEnv()
 	if err != nil {
 		return err