LCD to show DHT11 and DS3231 separately

Hi,
I’m trying to show time and date on LCD, then show temperature and humidity, and repate.
I tried to use “lcd.clear()” but it won’t work.

Here’s my code

#include <dht.h>
#include <DS3231.h>
#include <LiquidCrystal.h>


DS3231  rtc(SDA, SCL);
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
dht DHT;
#define DHT11_PIN A0

void setup() {
  rtc.begin();
  lcd.begin(16, 2);
}

void loop() {
  lcd.setCursor(0, 0);
  lcd.print("Time:  ");
  lcd.print(rtc.getTimeStr());
  lcd.setCursor(0, 1);
  lcd.print("Date: ");
  lcd.print(rtc.getDateStr());
  delay(1000);
  lcd.clear();
  delay(500);
  int chk = DHT.read11(DHT11_PIN);
  lcd.setCursor(0, 0);
  lcd.print("Temp.= ");
  lcd.print(DHT.temperature, 0);
  lcd.print((char)223);
  lcd.print("C");
  lcd.setCursor(0, 1);
  lcd.print("Humidity= ");
  lcd.print(DHT.humidity, 0);
  lcd.print("%");
  delay(5000);
}

What does that mean ?
What do you see on the LCD ?