7 Surprisingly Flammable Plants You Should Keep Away from Fireworks
Don't light the sparklers yet! These plants are sneakily flammable. Keep them away from fireworks (and your house) to avoid an unexpected blaze.
Summers have always been the hottest, driest season, but these days, with a warming climate, temperatures can become extreme. Most of us have seen our gardens dry out during summer, especially during periods of drought and/or high heat and – other than watering in the early morning – there’s not much to do about it.
As your landscape gets toasty and the plants get dry, fire risk increases. And that's not to mention 4th of July fireworks. If you’ve leaned into drought tolerant plants in the backyard, the risk is even higher given the lower moisture content. Some plants that are resilient in extreme weather can be surprisingly flammable, and wise homeowners keep these species far from homes, sheds, fences and other structures during hot, dry summer weather.
7 Garden Plants That Are Surprisingly Flammable
Some plants and trees are notoriously flammable and proud of it. We all know that pine and spruce needles have high resin content, and so do their branches and trunks. Other plants are just as flammable but a little sneakier about it. So don’t feel bad if you’re just hearing about their flammability for the first time.
It’s important to identify these “secretly” flammable plants because you just don’t want them near buildings or fences in hot summer weather. And you definitely want to keep them away from stray fireworks. We’d like to introduce you to seven of them that create quite a blaze if they burn.
1. Wild Lilac (Ceanothus spp.)
If you live on the West Coast, you are very likely to have a ceanothus in your backyard. These are among my favorite native shrubs, with the striking indigo flowers that cover the canopy in spring and attract butterflies, bees and other beneficial insects. The leaves are lovely too, small, oval and a dark, blue-green color. But not all ceanothus look alike. The genus includes some 60 shrubs, mostly evergreen, including some that are prostrate, some that mound, and some that are upright to 6 feet (2m) tall.
Another benefit of ceanothus is its drought tolerance; I’ve hardly watered mine since the first year I planted them. But this characteristic also indicates that these native beauties are flammable. In fact, ceanothus leaves are coated with flammable oils and resins. These garden staples started out as chaparral plants and nature built them for fire; the ceanothus seeds require intense heat for germination.
Few of us who love ceonothus are likely to cut our trees down because of an elevated risk of fire. On the other hand, it just makes sense to position it in the back of the garden rather than near the house, garage or shed.
Just in Case
2. Blackberry (Rubus armeniacus)
Fresh blackberries from the garden are sweet and delicious, but keep in mind that blackberry bushes are so flammable that they can be a fire hazard. You should never plant them close to your home, and if you have them in your berry patch, be sure to keep them manicured.
Left unattended, the canes can shoot up to 15 feet (5m) tall. They stay upright even after they die, creating scaffolding for new growth. The dead canes create a ladder fuel situation where a ground fire can climb up into tree branches. Replace your blackberry canes with red flowering currents, thimbleberry and Pacific crabapple.
3. Common Holly (Ilex aquifolium)
Deck the halls alright, but don’t plant common holly near your home. Its dark green, glossy leaves are unmistakable, but they are filled with resin and highly flammable. In a wilder landscape, they can also create a dense understory that can function as a ladder fuel. In addition, common holly leaves produce a flammable vapor when heated, making stands of holly a fire risk.
It’s wise to avoid planting holly near your home and don’t leave large holly piles near any structure. If you want to replace the shrub, consider sword fern, vine maple, or ocean spray.
4. Rosemary (Rosmarinus spp.)
Many of us have planted rosemary in the garden because it is extremely drought resistant and can take a hot sun. But this plant is among the more flammable of the native plants. Its needle-like leaves are filled with oils and resins - and these remain even when the needles die and dry on the stems. That translates to a plant that is appealing visually, useful in cooking, but highly flammable.
Most gardeners I know keep a shrub or two of rosemary in the herb garden, and this does not seem like a significant fire threat. But resist any temptation to suddenly install an entire bed of rosemary just beside your home.
5. Scotch Broom (Cytisus scoparius)
Scotch broom is considered a common weed today, but it was brought into America years ago as an ornamental. It is rather pretty, with leaves composed of three oblong leaflets close to the stem, slender stems, and a cloud of bright yellow blossoms from March to June. .
But admire fields of Scotch broom from afar rather than planting up your garden. Dense, mature stands of broom create lots of dead woody debris with a high oil content. This puts them on the “most flammable” list of plants that do not belong anywhere near your home or out buildings. Instead, plant native grasses and beaked hazelnut shrubs.
6. Lavender (Lavandula angustifolia)
My grandmother used to wear lavender perfume, and the whiff of this fragrant flowering plant brings back memories to me. That’s one reason I added it to my herb garden; another is that it is as beautiful as it is fragrant.
But as those slender, flexible stems turn woody as they age and dead plant matter builds up within the plant. This makes your lovely, fragrant lavender plant flammable, very flammable. It is not recommended that you plant lavender near any structure on your property. Keep it more than 5 feet (2m) away from your home to prevent any fire problems.
7. Bamboo (Bambusa vulgaris)
Now this one surprised me. Bamboo flammable? Well it is and it isn’t.
Bamboos are vigorous and dramatic plants with a tropical air. Their graceful swaying canes and forever foliage add structure and movement to the landscape. You can find bamboo that will be happy in almost every growing condition. Some are running and some are climbing but all seem flexible and moist rather than dry and flammable.
Live bamboo canes are made up of cellulose, and include high amounts of silica and water with very few volatile oils. Live bamboo is hard - if not impossible - to ignite, but the same cannot be said of dry bamboo. The dried stems, leaves, and sheaths of bamboo are extremely flammable, and most large stands of bamboo include lots of dead stems and dried debris. All this dry bamboo can explode when burned, so keep any large planting well away from your home.
You don’t need to remove bamboo from your landscape, but you do need to maintain it, pruning out dead wood regularly and removing it from the area. If this seems like too much work, consider planting something else like
Tips to Reduce Fire Risk
You can reduce the risk of fire in your home and landscape by selecting plants wisely and maintaining your garden. Here are five tips to keep in mind.
- Select plants that are fire-resistant, like succulents.
- Prune back branches that approach your home.
- Clean up and dispose of yard debris including dry leaves, canes, and branches.
- Never plant shrubs within 5 feet (2m) of the home.
- Choose mulch that is not flammable, like organic compost, instead of flammable mulch, like dried leaves or pine needles.
- Cut out dead plants, shrubs and trees promptly and remove them from the property.
