A recent review of our agave collection revealed several priorities for managing the collection.

Spacing pups

A high priority is spacing pups to accommodate growth.

Most mature agaves generate offsets (rhizomatous suckers) called “pups.” This is a vegetative or asexual method of reproduction. These are new plants that grow from the roots of a mature plant and are exact clones of the mother plant.

The quantity of these offsets varies with the plant’s species, age, environment, and whether it grows in the ground or a container.

Most agave species produce many offsets and eventually form into clusters. Some species, called “solitary” agaves produce few offsets or none when growing in habitat. When cultivated, however, even these could produce some offsets.

Some gardeners appreciate agave offsets and welcome the growth of clumps. They occasionally separate and replant the offsets to form a community of the given species. Another option is to give or sell the offsets to other gardeners.

In my garden, the need for pup management was accompanied by a desire to group a few specimens that had been randomly placed.

This column’s photos show the recent project to cluster selected agave species to form natural colonies for landscape effect.

Giving plants more space

Another priority involves moving plants from being crowded by large specimens.

Good landscaping practice includes installing plants at distances from other plants or walkways to allow for their mature sizes. Even after due diligence, some plants grow more significant than expected and become more prominent than appropriate for the landscape.

We have been growing six century plants (agave americana var. medio-picta ‘Alba’) from pups rather than discarding the pups or persuading other gardeners to grow these large plants. Predictably, they are becoming too large for the garden, so we plan to thin the “herd.”

We also have been growing several seedlings of an agave relative called Shishi hemp (Furcraea parmentieri). The seedlings grew from bulbils harvested from a mature specimen, which had grown almost as large as the century plant.

The Furcraea, like many agaves, is monocarpic: each rosette flowers only once and then dies. After the plant invests energy into growing its flower stalk, it topples to the ground and releases its new generation: many bulbils that root on their own.

A few agave species are polycarpic, meaning they will flower and set seeds many times before dying. My agave collection includes an uncommon polycarpic species with the common name maguey de la niebla and the botanical name agave polyacantha.

We will plant the Furcraea seedlings knowing from experience of how large this plant will become. We could plant the tiny seedlings close to other plants while planning to relocate the neighbors as the Furcraeas increase their sizes.

Rosette variations

Agaves are popular plants for gardeners to collect because of their range of sizes, colors and leaf forms. All agaves are rosette plants that have leaves growing in a circular or spiral pattern from a central stem (many other garden plants have leaves or blossoms in rosette form). Agave leaves cluster together at a similar height, usually at or near the ground.

Agave rosettes are typical of the genus, and the species vary in overall sizes, leaf shapes and coloration, and marginal and terminal spines. There are even a few spineless agave species.

This column’s photo gallery includes examples of these variations from my garden.Collecting and handling agaves

Plants of the agave subgenus agave have defensive spines — terminal, marginal spines or both — that can be sharp. These present a fierce appearance and require careful handling, but some gardeners find them appealing and uniquely attractive. Some gardeners are “agave-aversive” for fear of being poked. Their self-preservation priorities include leaving these attractive plants out of their gardens.

Spiny plants can be handled safely when using reasonable care. For example, a safe practice while moving a spiny plant involves wrapping it loosely in an old towel to shield its spines from the gardener’s hands.

Agaves can be safely grown away from walkways, weeded as needed with garden tongs and transplanted while wrapped in a towel. These techniques are not needed with most other garden plants, but they open the landscape to an exciting group of plants.

Advance your gardening knowledge

Visit Wikipedia.com and search for “agave” or “List of agave species.”

Browse Debra Lee Baldwin’s gallery of agaves (debraleebaldwin.com/agave-photos-labeled-identified).

Read the valuable reference book by Jeremy Spath and Jeff Moore: “Agaves: Species, Cultivars and Hybrids” (2021).

Seasonal garden projects

In response to a reader’s request, this column includes brief recommendations for current priorities for gardening on the Central Coast of California.

Plant cool-season vegetables and herbs: leafy green, root vegetables, brassicas, alliums (such as garlic and onions) and herbs.

Plant cool-season annuals: Iceland poppies, pansies and violas, primroses, snapdragons, ornamental kale and cabbage.

Plant spring-flowering bulbs to establish roots before blooming: daffodils, tulips, hyacinths, anemones and ranunculus.

In future columns, we will highlight other timely gardening priorities.

Enjoy your garden!

Tom Karwin is a past president of Friends of the UC Santa Cruz Arboretum and the Monterey Bay Iris Society, a past president and Lifetime Member of the Monterey Bay Area Cactus & Succulent Society, and a Lifetime UC Master Gardener (Certified 1999-2009). He is now a board member of the Santa Cruz Hostel Society, and active with the Pacific Horticultural Society. To view photos from his garden, facebook.com/ongardeningcom-56651 1763375123. For garden coaching info and an archive of On Gardening columns, visit ongardening.com for earlier columns or visit www.santacruzsentinel.com and search for “Karwin” for more recent columns. Email comments or questions to gardening@karwin.com.