What are the sun requirements for Lactuca sativa 'Parris Island Cos'?

Lactuca sativa 'Parris Island Cos' requires full sun to partial shade.

How much water does Lactuca sativa 'Parris Island Cos' need?

Lactuca sativa 'Parris Island Cos' has moderate to high water needs.

Annuals

Lactuca sativa 'Parris Island Cos'

Parris Island Cos Lettuce

UnknownMediterranean

At a Glance

Typeannual

Habitupright

Foliagedeciduous

Height10-12 inches

Width6-8 inches

Overview

Lactuca sativa 'Parris Island Cos' is a distinguished romaine lettuce cultivar renowned for its exceptional heat tolerance and superior performance in warm climates. This robust variety produces tall, cylindrical heads that reach 10-12 inches in height, with characteristic upright growth that sets it apart from other lettuce types. The dark green outer leaves are elongated and spoon-shaped, measuring 10-12 inches in length, with pronounced white midribs that provide structural integrity and contribute to the variety's signature crunch. The foliage displays a slightly savoyed texture on the outer leaves, which gradually transitions to smoother, more tender inner leaves that form a dense, blanched heart. This blanched interior is prized for its sweet, mild flavor and crisp texture, making it ideal for both fresh consumption and cooking applications. The sturdy leaf structure and thick consistency make Lactuca sativa 'Parris Island Cos' particularly suitable for grilling and wrapping, while its ability to maintain quality in warm weather extends the growing season significantly compared to heat-sensitive lettuce varieties.

Native Range

Lactuca sativa originated in the Mediterranean basin and western Asia, where wild lettuce species continue to thrive in their natural habitats. The cultivar 'Parris Island Cos' was specifically developed in the United States during the mid-20th century, bred for enhanced heat tolerance to meet the demands of Southern and warm-climate growing conditions.

Suggested Uses

Lactuca sativa 'Parris Island Cos' excels in vegetable gardens, raised beds, and large containers with adequate depth for root development. Ideal for fresh salads, Caesar salads, lettuce wraps, and grilled vegetable dishes due to its sturdy leaf structure. Perfect for succession planting every 2-3 weeks to ensure continuous harvest throughout the growing season. Works well in mixed plantings with herbs and other cool-season vegetables, and is excellent for market gardening due to its shelf life and heat tolerance.

How to Identify

Lactuca sativa 'Parris Island Cos' can be readily identified by its distinctive upright, cylindrical growth habit that forms loose heads rather than the flat rosettes typical of other lettuce varieties. The dark green leaves are notably elongated and spoon-shaped, with prominent white midribs running down the center that provide both visual distinction and structural support. Mature plants reach 10-12 inches in height with leaves growing vertically rather than horizontally, creating the characteristic romaine silhouette. The outer leaves display a slightly textured, savoyed surface, while inner leaves are progressively lighter in color and more tender. Key identifying features include the plant's ability to maintain structural integrity in warm weather without immediate bolting, and the thick, sturdy leaf texture that distinguishes it from more delicate lettuce varieties.

Appearance

Bloom Information

summer when plants bolt, typically after 85+ days in heat

Detailed Descriptions

Flower Description

small yellow flowers in tall spikes

Foliage Description

dark green with prominent white midribs

Growing Conditions

Sun Requirements

full sun to partial shade

Soil pH

6.0-7.0

Water & Climate

Water Needs

moderate to high

Time to Maturity

75-85 days

Care & Maintenance

Care Guide

Lactuca sativa 'Parris Island Cos' requires consistent moisture and well-draining soil for optimal development. Provide approximately 1 inch of water per week through deep, infrequent watering sessions, maintaining evenly moist but not waterlogged soil conditions. Apply a balanced fertilizer (10-10-10) every 2-3 weeks during the growing season, or incorporate 2-3 inches of compost into the soil before planting. Mulch around plants with organic matter to retain moisture, regulate soil temperature, and suppress weed competition. In hot climates, provide afternoon shade or use row covers to prevent premature bolting and extend the harvest period. Monitor for common pests such as aphids and flea beetles, and practice crop rotation to prevent soil-borne diseases.

⚠️ Toxicity Warning

Lactuca sativa 'Parris Island Cos' is completely non-toxic and safe for human consumption. All parts of the plant are edible, with leaves being the primary harvested portion. The plant poses no risk to pets, children, or wildlife, making it an excellent choice for family gardens and areas where safety is a concern.

Planting Guide

Planting Methods & Timing

Planting Method

both

Indoor Start

4 weeks before last frost

Direct Sow Timing

early spring, 2-4 weeks before last frost date

Days to Maturity

75–85 days

Plant Spacing

8 inches

Companion Planting

Good Companions

tomatoes

carrots

radishes

onions

basil

chives

marigolds

Avoid Planting With

fennel

broccoli

cauliflower