All seeds are like miracles. Seeds have miraculous life power in them. If you hold a seed in your hand, you cannot see the life. If someone asked you to prove that the seed had life, you would not take it apart. Instead you would plant it and nurture it.
Seeds have miraculous marking power, too.
If you plant squash seeds, you won't grow tomatoes. Kingdom seeds are miracles, too. They are gospels, good news stories. They are people. They are churches.