Jobs for This September

Jobs for September

Jobs outdoors

The University of Maine Cooperative Extension says the best time to apply lawn fertilizer is around Labor Day – see their really helpful video about environmentally-sensitive lawn care for more information and tips.

Baby your bulbs, take care of your tubers

Early September is a great time to lift your tubers, look after your bulbs and plant new ones.

Plant for Spring

You can plant spring-flowering bulbs as long as the ground is workable. The Old Farmer’s Almanac has a great chart to help you plant, but the general rule of thumb for planting Spring bulbs is to plant them nose up two or three times deeper than the bulb is tall (about 8 inches deep for large bulbs like daffodils, smaller bulbs like grape hyacinth more shallowly – remember Summer bulbs requirements vary), pressing them down into the soil to ensure there any gap under the bulb is minimized to prevent the bulb rotting.

Your Spring display is likely to last longer if you dig the entire area you intend to plant and press the bulbs down into the soil then cover them to the proper depth, but you can also use a bulb planter to cut a hole right where you want the bulb and recover it. You can select a formal layout for the bulbs or choose a more natural appearance by tossing the bulbs onto the area and planting them where they fall, but either way planting in groups or drifts is likely to be more pleasing. Water in your newly-planted bulbs to give them the best possible start.

Lift and store bulbs and tubers

Bulbs are best stored dry between 60-68°F. This means placing them loosely in paper or ventilated plastic bags with sawdust, vermiculite or sand and leaving or hanging the bags where they will get plenty of circulation.

Irises - Lift clumps of bearded iris with a shovel and break them apart, saving the plumpest, firmest rhizomes and discarding the old, leafless ones. Trim the leaves to about six inches long and let the rhizomes air dry overnight before replanting.

Daylilies - Clumps may be so dense you'll need to slice through them with a shovel or spade to create smaller clumps, leaving at least three plants per clump. Trim leaves to about six inches long and replant.

Dahlias – September might be a little early, but when the first frost blackens the foliage of dahlias (or if a hard freeze is predicted), it’s time to look after them for next year. Carefully dig the clumps with a spade or fork, cut the stems down to about six inches above the tubers and rinse them off. Let them dry away from direct sun and wind for a day (too much longer and they'll shrivel0). Store the tuber clumps whole, or carefully separate the tubers from the stem, making sure to include any "eyes" (small, raised nubs near where the tubers attach to the main stem) with each tuber, as the eyes are future sprouts. Store at around 35-50° F.

Keep Composting

Your compost heap will benefit from your efforts to clear up vegetables and flowers that have gone by, which will also help keep your veg patch disease-free next year. Chop up the waste and layer it on your heap with plenty of dried leaves, cardboard or newspaper and add an accelerant if you use one. Take care with weeds – unless your compost heap gets good and hot you may simply be removing weed seeds from your garden then spreading them with your compost next Spring. If you’re new to composting welcome! See our FAQ on how to get started for more advice.

Please remember that if you are going to burn any garden waste that you do it in keeping with local law and before any hibernating creatures have gone to sleep for the Winter under your heap.

Collect Seeds

It’s time to start collecting seed from dill, thyme, basil, bachelor buttons, lavender, hollyhocks, cosmos, some snapdragons and many wildflowers. If seeds are borne in a flower head, cut off the seed stalks just before the seeds are dry and start to scatter. Dry the stalk, then rub or shake the seeds off into a labeled paper bag for storage. If the seeds are in a pod-like structure, allow the pods to turn brown before harvesting. Dry the pods in a warm, dry site and then shell as you would peas. Label and store seeds in a cool, dry place such as airtight jars in a refrigerator.

Keep in mind that many annual flowers are hybrids, which won’t produce offspring like the parent plants reliably or at all.

Think trees

September is a great time to plant trees and shrubs, giving them plenty of time to lay down new roots before Winter and be ready to establish themselves come Spring. Remember to stake more fragile young trees if they need it to avoid Winter winds damaging roots, but ensure you stake them with something strong but forgiving to protect the bark and keep disease out (like an old bicycle inner tube in a figure of eight between the stake and the tree or a collar cut from an old hose around the guide wire). Place stakes outside the root ball and remove them when the tree can stand on its own, usually after a year or two.

Jobs indoors

You will need to bring house plants in from outdoors before nighttime temperatures dip below 45° F, but you’ll want to inspect them for disease and insects before you do so you can treat any problems before bringing them into your house. Soaking pots in a tub of lukewarm water for about 15 minutes will force insects out of the soil.

Repot any plants that need it, including into larger containers. If plants have gotten leggy during their outdoor stay, remove the container and prune the top and roots in equal proportions. Scrub the pot, add fresh potting soil, and replant.

To prevent shock when you bring houseplants back indoors, expose plants gradually to reduced lighting. If they are moved to lower light from bright light abruptly they are likely to lose some leaves, but these should regrow as the plant adapts to its new environment. It’s best if they've been outside in high light to put them in similar light indoors (like a south window or under plant lights on a timer for 16 hours a day).

Pesky pests – Tomato Hornworm

If you see a bright green caterpillar up to 5 inches long with pale chevron markings slashed down its sides eating your tomatoes, potatoes or other nightshades, you may have Tomato Hornworm (Manduca quinquemaculata), which grow into a mottled brown moth called “sphinx”, “hawk” or “hummingbird”. University of Maine Extension has images and information to help you identify the pest. Their size means they can cause considerable damage quite quickly, more so if they appear in large numbers, so it’s well worth being able to spot them to stop them before they grow and ruin your plants.

The good news is that you shouldn’t need chemicals to control them, and chickens love them, so if you keep hens they will help you get rid of them.


Understanding the lifecycle of the caterpillar can help manage them. Moths emerge in Spring, mate and lay smooth pale green eggs on leaves, where the caterpillars have a ready meal when they hatch. Caterpillars grow for 3-4 weeks then fall to the ground where they burrow into the soil to pupate and emerge in about two weeks to start a new generation of caterpillars around mid-Summer. These are the caterpillars most likely to eat your tomato plants before they also fall to the ground, burrow, pupate and await the following Spring.

Managing the pest is reasonably easy if you catch them before they do too much damage. Telltale signs of their presence include dark green droppings on the tops of leaves, missing leaves or white cocoons. The caterpillars themselves are well camouflaged, so a daily inspection of susceptible plants to look for eggs or small caterpillars will help. If you do find them, handpicking is very effective, and any hens you know will appreciate the snack. To prevent future infestations, tilling the soil at the beginning and end of each growing season is reported to have a 90% mortality rate for overwintering larvae. Encouraging beneficial insects like wasps that will parasitize the caterpillars is also important. Finally companion planting dill, basil or marigolds will keep these and many other pests at bay.

First Frost

According to the US Weather Service, the average first frost in Rockport is between October 1-10, and the earliest frosts occurring between 21-30 September.

The Old Farmer’s Almanac says the first 2017 frost date for Rockport is October 13 (50% probability based on 1981-2010 weather). You can check your area here

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