This little pest likes to hangout in sunny to partly shady areas with wet to moist soil.
The plant can be few inches to several feet high; stems are thick, sprawling canes with piercing thorns; leaves are dark green with notched edges; flowers are small, white blooms that turn to edible berries.
You'll begin to notice the plant in spring...and then the onslaught begins! New growth spreads rapidly, overtaking plants in the way. New growth can sprout where prickly canes touch the ground. One square yard can have over 500 canes! The root system is huge, storing food and sucking up water needed by other plants. Sweet-tasting berries ripen late in the summer, full of seeds ready to hitchhike in animals' stomachs to new ground. Birds are often accomplices to these perpetrators, since seeds that pass through their digestive systems may actually sprout more easily. In the winter, many leaves die back, but there's no killing this monster. It can survive on food stored in its roots.
WARNING! THIS IS A MAJOR PEST! NEW GROWTH CAN SPROUT FROM PIECES OF ROOT OR CANES, SO REMOVE AS MUCH OF THE PLANT AS POSSIBLE.
Leave the Brambles in Shambles!
Here's a plan of attack to follow:
1. Check out areas where accomplices like birds hang out.
Search out defenseless seedlings.
Make rounds frequently to nip any problems in the bud.
Take some notes on what you see, and especially where you see it so you can remember to return to invaded areas.
2. Other, less intrusive blackberry bushes can be mistaken for the Himalayan Blackberry, so make sure you know what you are dealing with.
3. This perpetrator may penetrate property perniciously, but it can be picky about the place. Himalayan blackberry shows a preference for wetter areas.
Seedlings are much more vulnerable than older plants, so destroying them when they're young is the key to warding off blackberry intruders.
4. Himalayan blackberry is extremely aggressive. It spreads quickly, crowding out plants in the way.
Think about where the offensive plant is, what other plants are near, how big it already is, and if you want to contain it, destroy it, or leave it alone.
Some people like having a small patch of berries to make jams, pies and syrups. But be careful, Himalayan blackberry is always ready to conquer new territories.
5. What to do...
-Dealing with an intense pest like Himalayan blackberry may be overwhelming. However, not counterattacking such a forceful intruder will guarantee a continually larger attack each year. Focus on cleaning up a small area and then keep working outward.
-The larger a blackberry patch gets, the harder it is to get rid of. So if you're thinking you might want to take steps against this pest someday, don't procrastinate.
-Don't hesitate-send in the S.W.A.T. team! Tear seedlings out of the ground as soon as you see them. Little seedlings are less likely to bounce back from attacks than bigger and stronger plants.
-Starve the robust root system by continually cutting down above-ground growth. You can mow large areas, but hoeing is better if the area is small enough. It may take a few seasons, but eventually the scoundrel will starve to death.
-Counterattack invasions after blackberry bushes flower, but before berries are produced. Repeatedly destroying above-ground growth at this point is key because underground food storage is at a low and new seeds have yet to be produced.
-Lots of critters eat blackberry, but unfortunately even their combined appetites aren't big enough to control this thorny scoundrel.
-If you decide to use chemical weapons, the best method is spot treatment-think of it as sharp shooting. For example, cut back the above-ground blackberry bramble as far as possible. Then only apply the herbicide directly to freshly cut canes.
-Do not use chemicals near blackberries that will be eaten.
Always read and follow the directions for use, storage and disposal of herbicides.
6. Were your measures effective?
With a pest like this, it is important to know whether your work was worth the effort or not. Write down in your gardening records when and where you treated for blackberry. Keep returning to these areas.