Gardening Information and
​Weather Outlook

Plant Hardiness Zones

Zones range from 7b in the north to 9a on the coast.
​Hardiness zones are based on the average annual extreme minimum temperature during a 30-year period in the past, not the lowest temperature that has ever occurred in the past or might occur in the future. Gardeners should keep that in mind when selecting plants, especially if they choose to "push" their hardiness zone by growing plants not rated for their zone. 
Many species of plants gradually acquire cold hardiness in the fall when they experience shorter days and cooler temperatures. This hardiness is normally lost gradually in late winter as temperatures warm and days become longer. A bout of extremely cold weather early in the fall may injure plants even though the temperatures may not reach the average lowest temperature for your zone. Similarly, exceptionally warm weather in midwinter followed by a sharp change to seasonably cold weather may cause injury to plants as well.

Mississippi Soil Types

In Mississippi, there are several major soil resource areas. These predominant soils and composite vegetation define major ecoregions across the state. These are the Delta, Loess Hills, Upper Coastal Plain, Blackland Prairie, Lower Coastal Plain, and Flatwoods.
 
Delta
The Delta region of western Mississippi is part of the Mississippi River floodplain. Soils here are moist to wet, with medium to heavy texture.
Loess Hills
Adjacent to the Delta to the east are the Loess Hills, formed from wind-blown glacial outwash some 10,000 to 12,000 years ago. These silty upland soils are deep, well drained, and fertile.
Upper Coastal Plain and Interior Flatwoods
The Upper Coastal Plain and Interior Flatwoods major soil regions are in the northeastern section of the state. The soils in these regions are older and more highly weathered, so they are less fertile than those to the west. These soils display advanced soil development, with well-defined topsoil and subsoil horizons.
Blackland Prairie
Interspersed within the Coastal Plains is the Blackland Prairie ecoregion. The Prairie soils bisect the northern and central portions of the state. Having developed from more chalky sediments, soils in this region are fine-textured with shrink-swell clays. Soil pH tends toward alkalinity.
Lower Coastal Plain and Coastal Flatwoods
In the southeastern corner of the state are the Lower Coastal Plain and the Coastal Flatwoods along the Gulf of Mexico. Predominant soils are sandy and wet with low native fertility.​