Tex. R. Civ. P. 658
Either at the commencement of a suit or at any time during its progress the plaintiff may file an application for a writ of garnishment. Such application shall be supported by affidavits of the plaintiff, his agent, his attorney, or other person having knowledge of relevant facts. The application shall comply with all statutory requirements and shall state the grounds for issuing the writ and the specific facts relied upon by the plaintiff to warrant the required findings by the court. The writ shall not be quashed because two or more grounds are stated conjunctively or disjunctively. The application and any affidavits shall be made on personal knowledge and shall set forth such facts as would be admissible in evidence; provided that facts may be stated based upon information and belief if the grounds of such belief are specifically stated.
No writ shall issue before final judgment except upon written order of the court after a hearing, which may be ex parte. The court in its order granting the application shall make specific findings of facts to support the statutory grounds found to exist, and shall specify the maximum value of property or indebtedness that may be garnished and the amount of bond required of plaintiff. Such bond shall be in an amount which, in the opinion of the court, shall adequately compensate defendant in the event plaintiff fails to prosecute his suit to effect, and pay all damages and costs as shall be adjudged against him for wrongfully suing out the writ of garnishment. The court shall further find in its order the amount of bond required of defendant to replevy, which, unless defendant exercises his option as provided under Rule 664, shall be the amount of plaintiff's claim, one year's accrual of interest if allowed by law on the claim, and the estimated costs of court. The order may direct the issuance of several writs at the same time, or in succession, to be sent to different counties.
Tex. R. Civ. P. 658