With the beautiful weather, we have gone ahead and planted petunias, geraniums, dahlias, marigolds, etc. but we are uncertain as to when they need to be covered at night. At what point will they be damaged by frost if left uncovered? Do newly planted perennials need the same protection? |
Those are good questions. Plant tissue can freeze when the temperature drops below 30 degrees F, but it would be a good idea to cover your plants whenever nights are expected to dip below about 40 degrees. This provides extra protection for especially cold-sensitive plants and also helps prevent delays in flowering. Polyester row covers provide good lightweight protection. Perennials are less likely to suffer damage, so they should be fine left uncovered. |