Lupines: Hardy Natives and Short-Lived Perennial Hybrids

Is there a garden plant that you have a love/hate relationship with?

I’ve got several, and one of them takes me back to my visits to the Chelsea Flower Show where several decades ago I saw a magnificent display of lupines. I believe they were the Woodfield varieties, and they were in full bloom, in red, pink, white and blue. Absolutely spectacular specimens and spectacular eye candy.

In some areas of England lupines grow really well, and while they are not long-lived perennials there, they are pretty reliable for several years of blooms. We had been growing them at our wholesale nursery, and I became even more fond of a dwarf variety called Little LuLu, which we offered in several colors. Then the seed became unavailable. We switched back to the taller Russell hybrids, which we grew in five colors, but as with Little LuLu the breeder of the Russells stopped doing the hybrid crosses necessary to perpetuate the line — and that was the end of that.

Unfortunately, we found there were two issues with growing lupines. The first problem was that our East End summers just seemed to get too hot for lupines to survive. Lupines are not heat hardy but are cold hardy, and while we could overwinter them, it was nearly impossible to get them to return and revive in the spring. At that point we only offered the native perennial lupine (Lupinus perennis) and had to drop ornamental lupines from our catalog.

This didn’t stop other growers from continuing to offer these plants, but now, some 30 years later, lupines, both dwarf and tall, seem somewhat rare at local garden centers. The Russell hybrids, also known as The Band of Nobles, were available in blue (Governor), white (Nobel Maiden), yellow (Chandelier), red (My Castle), pink (Chatelaine) and carmine (The Pages). These are all hardy but only in areas north of us where summers are cooler.

You will occasionally see seeds offered of the Russell hybrids, but they are always mixed colors because the pure lines and hybridization that perpetuates these lines seem to be long gone.

Several years ago a new hybrid began showing up and was developed by Westcountry, another British grower and hybridizer. Originally these were only available from a few growers in the United States as their inventory was tightly controlled as was their propagation. My first experience with this variety was when the White Flower Farm began to offer the variety Manhattan Lights which is a hybrid with bicolored purple/yellow flowers. It looked great in the pictures. It looked just as great in the garden. I tried three times over three years, and again another lupine that wouldn’t overwinter in spite of the claims of hardiness. Alas, hot summers do this one in as well.

There are some truths we have to deal with though. You can go to England and see outstanding displays of lupines, and my understanding is that most grown there do overwinter, but these are still considered short-lived perennials. In our country you can find nice lupine displays throughout New England, and there are lupines in Texas, Colorado and California that put on spectacular displays but for the most part tend to be annual types that self seed. So, what are East End gardeners to do?

In a word, experiment. If you really want to try some of the ornamental lupines and if you have any hope of having them last more than a year there are steps to take and considerations. First, start with small plants and allow them to grow in. Larger plants may be available at local garden centers as we go into the season but I don’t think these are the ones that will have much of a chance once exposed to our summer heat. On the other hand, you may find a microclimate on your property or within a garden that offers some respite from summer heat spells that could give these plants a chance.

The south side of a house that warms early in the spring and accumulates heat through the summer may not be hospitable. Neither will a fully shaded spot. Soil conditions will also play a critical part in any success. These plants won’t like a deep, rich, irrigated garden soil. They need good drainage, a soil made with well aged compost and or humus added. Go very easy on the fertilizer, and I suspect that liquid organics such as kelps and fish emulsions will suit them best.

Proven Winners offers several colors in the dwarf Gallery series, but these are only available through their online store which you can find here: provenwinners.com/plants/lupinus. These plants are sold for about $20 plus shipping and are shipped well developed in pots. They also sell several of the Westcountry hybrids online with a smaller selection that you may find at local garden centers.

A few weeks ago I included some comments in this column about pollinators (of the insect type) and the plants that these pollinators use to feed on nectar and also gather pollen. One of those plants I noted was the wild lupine (Lupinus perennis) that was once found as a native on the East End. As it turns out this lupine is now very hard to find commercially and some wholesale growers have been marketing the Western lupine (L. polyphyllus) as our local native. It is not. In fact, our native eastern lupine now appears to be supplanted by the western variety, and the National Park Service notes that in Arcadia National Park in Maine, L. polyphyllus has now crowded out the native lupine.

As for the native pollinator species L. perennis — don’t plan on a meadow full of these. I know of one project in Bridgehampton where one garden enthusiast planted an entire potato field with the seed of this lupine. The results were not as intended, and the project was abandoned. Another such project was done on a 5-acre plot in Westchester about 20 years ago and again the project failed. Both projects failed because of a basic lack of knowledge of the species (which does not grow in meadows) and the need for instant color and instant gratification.

You can purchase both the seed and the plants of L. perennis from Prairie Moon Nursery (prairiemoon.com). While the seed is not locally collected, I have confirmed that the seed is indeed from this species. My suggestion would be to try a few of the plants and to try your luck with the seed as well. Understanding the plant will be your key to any hope of success, and it would certainly be nice to see this plant reestablished on both the South and North Forks.

Remember that this plant is a legume and requires little to no fertilizer. It essentially makes its own by “fixing” and creating nitrogen in the soil on small nodules that develop on the roots. You don’t see much about this but I suspect that adding an inoculant (the same one you’d use when planting peas — also legumes) in a liquid solution when planting and some of the older literature suggests soaking the seed for 24 hours in an inoculant solution. Most garden centers sell small packets of the powdered inoculant.

Then there’s the challenge of germinating the seed. The lupine seed coat is very impervious and can take months to years to germinate in nature. There are some methods of speeding up this process of breaking down the seed coat. One is to lightly sand one side of the seed with a fine emery board. Another is to soak the seed for 24 hours in water and a third method is to nick the seed with a small triangular file — just nick it though. The seed is then sown in situ or in peat pots, but it can still take weeks to months for germination.

I’ve also read that you can scarify the seed by putting it in a rock tumbler that has pea gravel in it along with the lupine seed. I think the note said to tumble the seed for 24 hours but there was no clue to the speed of the tumble and the ratio of pea gravel to seeds, so again, an experiment for the curious.

I suspect that the greatest success will be if you treat the seed then plant the seed in the outdoor location where you hope the plants will establish. Do this both in late summer and again in early spring with the seed planted about a third of an inch deep with about five to ten seeds per square foot. Try several locations, water weekly and watch. It may take up to two years for your seeds to germinate and get established, but your pollinators will appreciate your efforts.

Oh, and here’s a big plus: Deer and rabbits will ignore your lupine plants. That alone may be enough to coax some of you into trying this and taking part in the experiment. In addition, the plants are virtually insect free with the exception of the lupine aphid. These are easily knocked down with one application of pyrethrin but before the flowers begin to attract bees. I have one lonely L. perennis plant growing in my Echinacea purpurea bed. I don’t recall where it came from but it’s at least 3 years old. It did produce some seed last summer but so far none have germinated. I remain undaunted though.

Many possibilities here for the gardeners out there who like to experiment and now that you have the knowledge all you need is some seed, some plants and some patience. Let me know how it goes and of course, keep growing.