Great Gunnera


QUICK REFERENCE PLANTING GUIDE

1. Light/Sun Exposure - Full sun to partial sun.

2. USDA Hardiness Zones - Garden hardy in-ground in zones 7-11.  In cooler zones (1-6), they should be lifted in the fall.

3. Planting Distance - 5 to 6 feet apart in ground.

4. Mature Height/Spread - 9 feet with an 8 to 12 foot spread if left in ground undisturbed for 3 to 5 years.

5. Bloom Time - Summer.

6. Planting Instructions - Dig a hole twice as wide and twice as deep as the bare-root plant that you received. (See illustration at right.) Remove the plant from its plastic bag and carefully place the root into the hole, with the top (crown of the plant) level with the soil surface. Refill with soil mixture. Firm the soil around the plant with your fingers. Water thoroughly.

GET THE MOST ENJOYMENT

Great Gunnera is an enormous plant usually seen at the water-side or in wet soil. Bold, rich green leaves grow amazingly fast until they are up to a height of 9 feet with an 8-12 foot spread. They are best suited for in-ground use as a border or screen, preferably in moist or wet areas or where they can be easily watered. In the summer, corn-like flower spikes of greenish-bronze appear and remain until fall. Gunnera could be used in containers for 1 or 2 years, but will quickly out-grow its pot. What a dramatic statement these exotic, stunning perennials make in the garden, where they have room to grow and flourish.  

Hardy in Zones 7 and higher, Great Gunnera needs winter protection in colder climates. This can be accomplished by a heavy winter mulching or by lifting and storing during the winter months.

SOIL PREPARATION

Although these plants will perform well in average garden soils of all types, we recommend having your soil tested periodically by the local County Extension Office.  These tests can determine if the soil needs any amendments to enhance your plants' growth and performance.  See below for our recommended practice to improve your soil without any additional testing:

1.  Spade or till the soil to a depth of 12-18 inches.

2.  To provide nutrients and improve drainage, add organic matter to your soil by mixing in a 2 to 4-inch layer of dehydrated manure, garden compost, shredded leaves, and/or peat moss.

3.  After active growth begins, periodically feed with Cottage Farms' water soluble Carefree Bud-N-Flower Booster. Plants in containers need more frequent watering and feeding, especially when in active growth and bloom.

CONTINUING CARE

Water - Your plants require 1" of rainfall (or equivalent watering) each week when planted in the ground.  Do not allow plants in containers to dry out.  In a container that is exposed to full sun, water it well at least once every other day, and possibly every day, during periods of intense summer heat.  You may wish to temporarily move containerized plants to an area where they are shielded from the hot summer sun (i.e., in the shade of a tree, on a porch near an overhang).

Mulching - Apply a 2-4 inch layer of shredded bark, compost or other organic mulch around your plants to promote moisture retention, maintain even soil temperatures, and to discourage weed growth.

Weeding - Keep the area around your plants free of weeds. Weeds compete with all plants for food, water and light. Walk around the garden periodically and pull weeds, including the roots, as soon as you see them.

Grooming - Clip off dead or unsightly growth to maintain attractive form and shape.      

Feeding - Feed your plants once every 2-3 weeks during the growing season with a water-soluble fertilizer such as Cottage Farms' Carefree Bud-N-Flower Booster.  Discontinue feeding after September 1st so your plants can harden off for winter dormancy. Resume fertilizing when new growth appears in the spring.

Winterizing - In zones 7 through 11 you can leave these bare roots in the ground provided they are mulched through the winter months. Cut the foliage down after the first killing frost and cover with a 2-4 inch layer of leaves, compost or mulch.

In zones cooler than 7 (1-6), the bare roots should be dug up or lifted before the first killing frost and stored in dry peat moss, perlite, or vermiculite in a location where the temperature stays around 40 degrees F.  Replant each spring after the danger of frost has passed.

Containerized plantings can be moved indoors to a cool spot (i.e., unheated garage, shed) in winter where the plants will go dormant in the container.  Water them lightly every 7-10 days.

In spring, remove mulch from in-ground plantings and bring containerized plants back out into the garden sunlight where they will immediately begin to repeat their yearly garden performance.

 

CAUTION: Not all plant material is edible. Though most plants are harmless, some contain toxic substances which can cause headaches, nausea, dizziness, or other discomforts. As a general rule, only known food products should be eaten. In case of ingestion, please contact your local poison control center at once and advise them of the plant ingested. Keep out of reach of children.