September Garden Tips


    Weekly Garden tips for Massachusetts Gardens

    September Horticultural Hints

    Topping your tomato vines at the beginning of September will make the plant put its enerrgy into ripening fruitTop your tomatoes
    Most varieties of tomatoes are ‘indeterminate’, meaning the vines that will keep growing until killed by frost.  By cutting off the top of your tomato plants down to where fruit has already set, you encourage the plant to put its energy into ripening the fruit already on the vine rather than generating new leaves and flowers.

    Check those leftover seeds - circledEnjoy vegetables this fall
    It’s not too late to plant some vegetables for fall harvest.  Start by inventorying your leftover seeds.  Do you have peas, spinach or lettuce?  Plant them now; they have plenty of time to produce a crop.  How about Tokyo turnips?  They are ready to harvest in a month.  Read your seed packages with an eye to ‘days to maturity’ then count back from the first frost date, mid-October for most of us.

    Plant a cold frame with vegetables for October and NovemberRow covers are back in fashion
    The row covers you used in May and June to keep out bean beetles and other bad bugs can be pulled out again, this time to provide a few degrees of nighttime protection against cold.  Check your town’s swap area for a hard plastic or glass covers (old doors or windows work well) to give you a simple cold frame that can keep your garden growing until covered with snow.   You can add 60 days or more to your growing season.

    Diseases like leaf mold on this tomato plnt make it a candidate for the dump, not the compost pileWhat to compost, what to bag and discard
    As you remove spent plants from your vegetable garden, look at each one with a critical eye.  Send any plant that is either diseased or infested with bugs to the dump.  Compost the clean plant material to create ‘Black Gold’ for next year’s garden.

    Pull out crabgrass before it has time to spread its seedsClean up your yard
    Take advantage of cooler mornings and evenings to do the weeding we avoided in August.  If it seems like weeds were the only thing that managed to grow during the drought, it isn’t an illusion.  Weeds such as crabgrass thrive in dry soils.  Reward that hardiness with a good tug and a trip to the dump.  Every weed that goes to seed means many more to deal with next year.

    Don't be in a hurry to rake the leaves that collect under shrubsThink twice before you rake
    While cleaning your yard remember the leaves that fall are food for the plants.  Use a mulching mower to chop up the ones on the lawn.  They will finish disintegrating over the winter.  Under bushes and around perennial beds, fallen leaves serve as a winter mulch and a home for many beneficial insects like butterfly caterpillar so please don’t chop them and leave them be.

    Freshen up your containers for fall with heucheras and grasses - not mumsFreshen your containers
    It has been a tough summer for plants in containers.  The unrelenting heat and the regular dousing with chlorinated tap water (in place of the non-existent rain) is not conducive to a long happy life for your annuals.  It’s too early to use cut evergreens, so consider putting in some transitional plantings such as the multi-colored kale, perennial grasses and heuchera.  Avoid using mums.  They aren’t a good choice if you like to keep the season going until Thanksgiving because the flowers will die long before that.

    September is the perfect month to divide perennials, like this hostaDivide and multiply
    September and October are great months to dig and divide overgrown perennials that bloom early.  Creeping phlox, oriental poppies, foxglove, delphinium and iris are all candidates.  You can also dig and divide later blooming plants such as hostas and many ground covers.  Spread them around your property, share them with friends or pot them up for your garden club’s spring plant sale.  They will be healthier and look better if you don’t wait until spring.

    Grass-EBenign neglect for your lawn
    The summer heat and water bans have been tough on everyone’s lawns, but don’t try to rehab them this autumn unless Mother Nature suddenly provides us with lots of rain and the watering bans are ended.  Apart from pulling crabgrass and other obvious weeds before they set seed, leave your lawn be. Grass is a hardy, cool-weather perennial, and there are steps you can take later this autumn and next spring to enhance your lawn.

    Planting-bulbs-ESpring bulbs?  Not yet, but soon
    Wait until the soil temperature has dropped to 55 to 60 degrees several inches below the surface to plant spring bulbs.  This usually occurs after several weeks of nighttime temperatures in the low 50’s.  Putting bulbs into warmer soil may cause them to begin growing tops (which is bad) when they should be growing only roots to support the flowers next spring.   Now is also a good time to dig up any bulbs that have been in for a few years. You’ll likely find they’ve multiplied and are now crowded (yeah! free bulbs) and need to be thinned; or have been attacked by moles, voles and other varmints and need to be replaced.  Add lime over old and new bulbs now, but fertilize only after they are in bloom in the spring.

    Save annual seeds for planting in the spring: annual poppies, nicotiania, larkspur, butterfly weed, verbena bonariensis, milkweed, etc. . or leave seed heads of self seeding annuals in place to have seedlings emerge next spring. Leave seedheads of plants that are attractive to birds: coneflowers, blackeyed susans, sunflowers.

Take cutting of coleus, petunias, fuchias and geraninus and others to grow inside in a sunny window or under lights this winter.

Transplant and/or divide peonies and daylilies now so that they will have time for roots to develop before the ground freezes.

Do not prune spring blooming shrubs now as their flower buds have already formed.

Leave broccoli, spinach and kale in the garden to harvest on past the first frost.