North Shore Gardener December 2008

Photo: F. Cunningham

Dec 3:Perennial hibiscus ,Peonies and mold, Japanese iris, Seeds from hosta, Carefree Garden

Perennial hibiscus
Q: I have had this perennial hibiscus in a container since purchase last summer. Is it too late in the season to plant it in the ground now? Or if I keep it in the container, do I bring it into the basement or the house? And how do I care for it during "dormant" season? Sun? No sun? Water? I have an office that I don't heat except on certain days - would this cooler environment be better? Since I am considering moving next summer I am inclined to keep it in the container until then, if possible.

A: It's really too late to plant the hibiscus outdoors unless the weather remains very mild for the next three or four weeks - I wouldn't chance it. It should have been planted earlier - then relocated to its new home next summer.
It won't be easy - but try growing it as a houseplant this year on a sunny window sill - expect some foliage loss and very few flowers, if any. If it looses all of its leaves, decrease water until spring and don't fertilize until the plant shows new growth. Also, light won't be as important if there are no leaves.
About that office:
How cool is cool??? I wouldn't let the temp drop below 60 degrees or so.....
And do keep the plant away from forced air vents - they're dry heat!
Keep your fingers crossed - this is not a houseplant. but there is little choice - it would have needed warmer growing time to get adjusted if you choose to plant it outside this late in the fall.........

Peonies and mold
Q: I have these amazing shocking pink peonies that were here when I moved in 23 years ago and have probably been here for decades before that. I transplanted a couple up to my house in Rye, NH, about 5 years ago and they have been thriving there, as well. This year for the first time, and only just recently, I noticed what looked like a milky-spotty coating on the leaves at the end of the season, as if they'd been sprayed with something. Is this something I should worry about? I am about to cut them down to the ground for the season and know to rake all the dead debris away from the plants (which I probably learned from you!). Should I do anything else?

A: Aren't you lucky to have all those brilliant pink peonies! Did you know that peonies are "deer-proof" as well as beautiful?!
Don't worry about the mold on the peony foliage - with the cool, damp fall it was bound to happen - and it will undoubtedly happen again next year! Just be meticulous in your fall clean-up. Cut - AND DESTROY - any and all affected foliage! -a little extra work for you, but worth it to prevent the mold spores from over-wintering in your garden. You could also lightly scratch in a handful of bone meal around the peonies (keep it about 6-8 inches away from the stems...) - it's good nutritional insurance for the start of the growing season next spring.
Transplanting your peonies has set them back at least a season or two, so don't despair if they don't bloom next summer - they will survive and be with you for the coming decades!

Japanese iris
Q: I have three groups of the early flowering iris in different parts of my gardens last year. While they all come up strong and green, none bloomed. They are all in 6-7 hours of sun. I have fertilized them every year with different fertilizers. What am I doing wrong?
M.A.P., Andover, MA.

A: Are you fertilizing too much - and with the wrong kind of fertilizer?
If it's a high nitrogen fertilizer, you're feeding the foliage, not flowers. This type of fertilizer is often used in spring lawn green-up formulas, and seeps into nearby flower beds, producing wonderfully healthy foliage - but few flowers!
Japanese iris need an acid fertilizer and plenty of water until after the blooming period - fertilize with a formula sold for azaleas and rhodys, like MirAcid - and water heavily through the spring and early summer - remember, these iris thrive in swampy areas! Reduce to normal watering through the late summer and fall after bloom, so roots don't rot...
Don't be afraid to cut flowers - but allow the remaining foliage to mature......

Seeds from hosta
Q: I have beautiful hosta, "Francis William” that blooms white flowers. This year when the flowers wilted, I removed the stalk and the seeds allowed to dry. The pods opened revealing black seeds. If these seeds are planted, will they yield anything?
If yes, when to plant?
Thanks, A.P.

A: Yes, you can grow hosta from seed!
Usually the seeds are gathered after ripening on the stem - but if they are black, they should be viable seed!
You certainly can grow them - but don't be surprised if what you get isn't exactly like the plant the seeds came from - these seeds were "open pollinated” that is, pollinated at random by bees! So you may be in for some surprises!
Many gardeners grow them right in the garden, allowing the seed to fall to the ground. Mulch very well over the winter - by spring, there should be germination under the rotting leaves.

A better, safer way would be to grow them indoors this winter:
Start with a good, packaged soil mix (like Miracle-Gro potting mix for seedlings) in a tray and moisten it well. Sprinkle the seed over the top of the soil and lightly cover - then mist to moisten the top soil.
Put the whole tray into a plastic bag and place on a heating mat to speed germination - light is not important at this time. It takes a week to ten days to germinate (don't be too disappointed if germination never occurs - sometimes seed is not viable and you'll have to try again next year!
After germination occurs, remove the plastic bag and give them plenty of light, about 10-12 hours a day) using grow lights if needed.
Transplant into small individual pots as they increase in size, keeping them evenly moist. -And by May, you'll have small plants ready to go outside - you'll probably have enough to give all of your friends and neighbors!
And you may get some new variations that no one has ever seen - and you will have the right to name the new hosta after yourself, “hosta Alma P"!

This week’s dirt…………………………………………………………
Bittersweet disposal
What are you going to do with the bittersweet you had on the table for decoration at Thanksgiving? Or with that wreath of bittersweet hanging on the door?
As beautiful as it is, bittersweet is an invasive species and must be treated carefully so you aren’t guilty of spreading the seeds around the neighborhood. When you are through with bittersweet, don’t throw it on the compost heap, where it will live and thrive forever – or could be eaten by the birds and carried far and wide. The best way to rid yourself of bittersweet is to burn the branches – or place them carefully in a dark colored trash bag and leave it in the sun till next summer – the dark bag will absorb the heat and kill the seeds. Heat kills these seeds – freezing weather won’t!

Dec 10 : Hosta,Violet ID, Oak tree, Raspberry Bushes, Winter care of roses

Hosta
Q: I have sent pictures and have a couple of questions about some plants I have. The first is a flower stalk of a hosta that grew this summer. I have never seen that before.

A: Yes - that was a flower stalk on your hosta - and no, it not unusual at all to see them bloom! Hostas are white and lavender to purple - and some are even scented! You will see more and more blooms every year as your plants mature.

Violet ID
Q: This is a small plant that grows in my yard. I`m looking for the name. It has a small blue flower in the spring and has a bulb like root. It also spreads like crazy and I `m constantly thinning it.

A: The little plant appears to be a common violet - you'll find them all over New England in the spring, blooming in purple to white and even some yellow. They spread by seed and by that underground root you mention. Some gardeners can't get enough of them - and some gardeners can't get rid of them soon enough! They can be a real pest if they take over a lawn or flower bed - but they are pretty!

Oak tree
Q: I enjoy your well-written column. Our front yard huge oak tree has produced about 5 times the number of acorns this year compared to other years. For many weeks many squirrels have climbed the tree and cut down small branches by the dozens daily-some with acorns, some without. The yard was mess even ‘tho we picked up daily. It has finally subsided. My question: what caused this? Around town we have seen no other oaks like ours. The other question: Are oak leaves taboo for a compost pile? Thank you for your help.
J.M.

A:- Hasn't it been a good year for acorns?! It is said that this means we have a hard winter coming: The reason? The tree seems to now what’s coming and produces extra food for wildlife - and also the tree produces lots of extra seed for self-preservation if we’re going to have a miserable, killing winter. We'll have to wait and see about that!
I can't explain why the squirrels are chewing down the ends of the branches - maybe to make it easy to get to the acorns?
Oak leaves can certainly be composted. They contain tannic acid which makes them very tough. But if you shred them they won't take any longer to rot than any other material in the pile....if used whole, they'll take a year or more to rot, even in a very hot compost pile. Keep in mind: Smaller leaves and materials will always compost faster.
For the same reason, oak leaves are not the first choice to use whole as mulch on the garden - shred the tough leaves and they can be as useful as other leaves as mulch if you plan to use them that way.

Raspberry Bushes
Q: I have a question about my raspberry plants. I transplanted them this year and have some that are fall bearing and the others bear earlier in the year. Of course, I am not sure which is which! What should I do to these plants to prepare them for the winter? Do I need to prune them in some way now?

A:You are right! Raspberries fall into two categories, summer bearing and everbearing or fall bearing - the fall bearing aren't really everbearing in New England since the cold weather comes too soon for them to bear their second crop in most years. Fall raspberries bear their crops on last years wood, the summer bearing raspberries bear on second year canes, canes which sprouted last year. Canes that bore fruit last year won't fruit again.
You have a choice: Prune in late winter or early spring, before the buds swell. (Old canes have grayish, slightly peeling bark).Use heavy gloves - raspberries have wicked thorns!
Also - you will want to prune any canes that sprout outside the area you have designated as your raspberry patch - do this faithfully each year, as raspberries can take over a garden!! And a more open, row-type of planting, which gets good air circulation, is healthier for the plants - and makes it far easier for their care.

Winter care of roses
Q: I have two roses which I put in this year – to prepare them for winter should I cut them way back – they are small.
Thanks so much!
L.R.

A: Rose care is simple, but you did not tell me what kind of roses you planted, so this is very general -if you are unsure about the variety, it is better to err on the side of caution.
Roses must be protected from changing and extreme temperatures and cold dry winds through the winter months.
Water well right up until the ground freezes. Tie up the branches with loops of soft twine, then mound up the soil 8-12 “around the base of the plant. (Be sure to take this extra soil from someplace else in the garden - don't just scrape it up from around the base of the plant since this will dangerously expose the roots!)
Surround the mounded bush with a cylinder of chicken wire or tar paper and fill with peat, or bark mulch. Leaves are not recommended since they get wet and mat down, causing molds and fungus. You can mound up additional soil to help anchor the cylinder and keep it in place for the winter.
Remove any winter protection before the buds begin to swell, usually before the last frost dates in April.

This week’s dirt…………………………………………………………
Start paper white narcissus bulbs! You’ll want plenty for holiday gift use. Narcissus bulbs are beautiful inexpensive gifts, even with the cost of bulbs up this year to $1.00 to $1.50 per bulb….
What else do you need? A pot and something to grow them in, like bark mulch, traditional white pebbles, or gravel.
They require no chilling in order to bloom! Start now, they'll be in bloom in less than three weeks, depending on the temperature of your house. Keep them cool, and they may take longer to bloom – but they’ll last longer and grow stronger flower stalks as well.
Need a really last minute gift? Don’t even plant the bulbs!
Give the bulbs, pebbles and pot wrapped in a colorful shopping bag. Include instructions on how to plant - let the recipient enjoy the planting!
Planting for your own enjoyment? Don’t plant all of the bulbs at the same time – plant at two week intervals and you’ll have flowers all winter – planting narcissus is a great fun project for the kids, too.

Last call! Baby, it’s cold outside!
Are you planning to buy a live Christmas tree this year? A live tree that is potted or burlapped isn’t much more expensive than a cut tree – and will be a part of you landscape for years to come.
Right now, before the ground freezes solid, hurry outside with your shovel– and prepare a planting hole for that live Christmas tree. Dig the hole – and cover the hole with boards and a thick layer of straw or hay and a tarp and it will be ready for you to uncover and plant right after the holidays. Save the dirt from the hole in a frost-free place in a plastic bag or a trash can so you will have unfrozen soil to use when it comes time to plant.
To avoid damage, please don’t keep a live tree in the house for more than a week and remember to water it regularly.

Dec 17: Garden gifts for kids, Moldy soil, Soil gnats

Garden gifts for kids
Q: I see a very few things marketed to kid’s gardening – some miniature pots with seeds for annuals, and things like mini greenhouses. Are they worth buying? I want to encourage my children who are just school age, to teach them the responsibility of taking care of a living thing. Are they worth it – they seem high priced considering the price of a pack of seeds. What can I give them now that they can grow on a sunny windowsill?

A: Many of the kits for kids are just guaranteed to disappoint them – and that’s not the sort of encouragement/start you want to give them. Start with a simple gardening gift that is guaranteed to bring success: plant some paper-white narcissus which are virtually fool-proof or for a really spectacular present, plant an amaryllis bulb. Make your own kit: supply the pebbles or potting soil and the pot and show the child how to place the bulbs in the pot. Stress the need for water, as well as light and warmth – and watch the smiles as they see their plant grow – guaranteed! Then later in the winter, graduate to bean sprouts in a jar, or grass on a sponge or a brick – simple and cheap and fun!
Next spring we’ll be again giving you some hints for simple veggie the child can plant in even a tiny garden – or even in pots. But for now, give the child the confidence of guaranteed success with a flowering bulb.

Moldy soil
Q: I have three philodendrons and the soil started to grow mold a few months ago in all three pots and I don't know why. I re-potted them this spring but none of the other plants I re-potted grew mold and I used all the same soil. I only water them once a week or as needed. I am afraid if I don't re-pot them soon the mold will kill them.
What could have caused this?
Thank you,
K.M.

A: You repotted - but was the soil you used sterile soil? All bagged soil, unless it's stated on the package, is not sterile!
Two choices: Buy a new bag of sterile soil and repot again - this time, rinse the whole plant, especially the roots as you repot - believe me, it won't hurt a philodendron!!
Or: you can remove the top inch or so of soil and replace with fresh sterile soil.
Then - Don't overwater the plants - (everyone tends to do this with a philodendron!) And when you do water, water early in the day, so soil has a chance to dry out.
Increase air flow around the plants - and increase the light levels. Keep plants cooler - molds love warmth!
Be sure to keep the plant clean - molds thrive on decaying matter, leaves, etc.
If you have the space, keep them away from other plants until the mold is under control - molds spread through the air by spores.

Soil gnats
Q: I read your gardening column in Salem News, and find it very informative. I have a question for your consideration.
I’ve noticed tiny flying insects buzzing around some of my plants, particularly in low-light areas of the house. These flying insects are very small and look similar to fruit flies. They seem attracted to the mold on the outside of the pots, as well as the top part of the soil.
Concerned that I had a harmful infestation in progress, a few months ago I removed and changed the potting soil and sterilized all the pots with boiling water. The insects have lessened, but are still around. The plants don't seem to be showing any significant negative effects. However, I have some more valuable, delicate tropical plants in other parts of the house, and worry about potential damage to them.
I tried spraying some of the low-light plants with an organic insect killing soap spray, but it appears to have been too harsh and damaged their foliage
Thanks and best regards,
S.M.,Salem, MA

A: The bugs are fungus gnats - they live - and reproduce - every few weeks in the top inch or two of moist potting soil. Most biologists agree that they won't hurt a healthy plant, but could damage the roots and foliage of plants under stress.
When you changed the soil, what did you use to refill the pots? I hope not rich, humus-filled garden soil because this is not sterile - and lots of organic material is just what the gnat larvae live it! Use only sterile potting soil when you repot to avoid gnats and many other indoor problems!
You can probably kill the gnats by with drenching the soil with a solution of 2 tsp.dishwashing soap in a gallon of water - repeat every few weeks as long as the gnats are visible.
Or you could also use a plant spray containing neem oil, or you could hang yellow sticky cards around the plants, changing them often as they fill up. Be sure to keep plants clean of all dead or dying vegetation and don't overwater!
Allowing the top inch or two of soil to dry out for a week or two and cultivating the surface carefully will kill the larvae in your soil and not allow reproduction to occur... Increase circulation in plant-growing areas - use a fan in cold weather when you can't open a window.
Quarantine the buggy plants until the matter is cured – bugs will certainly spread if conditions are right. After all that, your plants should be fine!

This week’s dirt…………………………………………………………
Friday is the official first day of winter – but don’t despair! It means there are ninety- one days of winter to come – but it also means that it’s only 13 weeks ‘til spring!

Now back to holiday business – and some last minute gifts for gardeners on your list:
Hanukkah is Dec 22, and Christmas is Dec 25 – be ready with these last-minute gifts:

Give some narcissus bulbs – 1 or a dozen, some pebbles or soil – and a pot to grow them in….package them in a colorful bag…

Make a gift basket for a gardener – you set the price limit - tuck in little things every gardener uses: Twine, plant markers, pots, saucers, seeds, etc – some small garden tools if budget permits.

How about a rooted cutting of one of your favorite plants? – An ivy or your favorite Christmas cactus or African violet - or at least the promise of a cutting later in the spring!

A simple notebook to use as a garden diary….kids can make this! Cut and paste pictures from old seed catalogs to decorate the cover…

A pot of grass for the cat in your life or a neighbor’s – it might save the houseplants or the cat from harm. Give the kitty a plant of his very own to safely nibble….

Short of cash? The very best gifts cost nothing but your time:
Give a very personal gift certificate or coupon book for services you will render: – lawn and garden services like mowing and weeding or planting or raking, dog-walking, vacation care of houseplants – you can think of more! This gift is particularly appropriate for a senior or shut-in friend -or for a child to give to a teacher or friend or neighbor...
Merry Christmas and Happy Hanukkah!

Dec 24:

This picture of the little tree is my own Christmas card – and it is sent today to all my readers. The illustration was first published in 1984 – and every year, I send it to each of you. Over the years, the number of cats in the tree changed - and so has our world…….
Joy to the world! And may there someday be Peace on Earth.
Merry Christmas to all!
Barbara Barger and Ruffles, the cat

Dec 31: Hibiscus, Oxalis, Cut flower preservatives, Christmas cactus bud drop

Hibiscus
Q: I just inherited a two-year old tropical hibiscus from a friend! It is inside, in a room that is about 64 degrees and gets tons of diffused sun. It seems very happy except for the yellowing and falling leaves. I'm pretty sure it's fairly normal for many of the leaves to yellow and fall off after the shock of being outside and then bringing it in, abruptly. Toward the last half of the branches are happy, green leaves and beautiful peach-colored blooms and buds.
My question is about when to prune this back and repot, as it is very leggy and root-bound. In the pot, the plant stands about five and a half feet tall, so it's pretty big!
Thanks for any help! I've never had a tropical hibiscus before!
Thanks again,
L.F.

A: What a nice inheritance! Prune the plant as you bring it into the house - you may need to prune it to fit your space!
Yes, unless you can give the plant a lot of sun during the winter - or if you use grow lights- it IS going to lose a lot of leaves and produce few flowers - but remember, they bloom on the new growth, so spring growth is the most important to you. During the winter, give least four hours of direct sun - a southwest window and a grow- light would help...normal house temperature is fine for the winter!
Hibiscus like to be pot-bound to bloom well, so don't be too quick to repot. Instead, in the spring, remove an inch or two of the topsoil and replace it with new bagged soil with fertilizer - do this as new growth begins in early spring. As a rule, fertilize during the growing months from March to October. If repotting is necessary, trim a few roots to relieve the girdling or circling of roots which can strangle to root system - don't ever remove more than a quarter of the roots at a time!
Keep the humidity up to discourage pests, like spider mites and aphids. Don't let the plant stand in water. Use lukewarm water when watering so you don't chill the roots!
Did you know that hibiscus plants have been known to live for 40 years??! You may have to write your inherited plant into your will!

Oxalis
Q: I have had a white flowering Oxalis for three years now and it is growing very well - except - this year after having it outside on our 3rd floor condo deck, I brought it inside. While it was outside I noticed white spots on the leaves which got to be the size of a dime. I have sprayed it but the spots keep coming and the leaves turn brown and eventually die. Help!!

A: Yes, it's rest time for many plants - the weather is getting colder, and the light levels are going down with every day. The oxalis probably has a fungus - why not try drying the plant out and allowing the little bulbs to go dormant, so you can remove the leaves after they yellow? Wait a few weeks - then replant in fresh soil. You should have regrowth in a matter of a few weeks -and flowers soon afterwards

Cut flower preservatives
Q: I have a lot of cut flowers during the summer season. How can I make them last longest? Should one use those packets of dry chemicals from florist shops? What are they? You hear rumors of sugar, also bleach or fertilizer. What is cheapest and most effective if you have a lot of cut flowers? I want them to last!

A: There are many home recipes for cut flower preservatives, whether they are garden-grown or store–bought flowers. All include some sort of a disinfectant, like bleach, and some food for the cut flower, like a sugar (The packets from the florist contain basically the same thing - and are very convenient) –but they all assume that you follow certain basic rules for all cut flowers and greens – the universal rule is cleanliness!:

Use warm water in the vase - it is absorbed easily!
Use a clean vase - change water - and wash the vase every few days...
Cut a half inch off the stem every few days – cut stem on an angle – it will allow better water absorption. Re-cut the stem every time you change the water to allow maximum water absorption....
Remove any foliage below water line to prevent rotting!
Keep flowers in a cool location - avoid the top of electrical appliances such as a TV or a microwave as well as hest vents and radiators.
Keep flowers away from fresh fruit, which exude a gas which will cause them to mature - and wilt faster....

While you wait for next summer’s crop of cutting flowers, here are three "kitchen flower preservative recipes" to try on bought flowers. Try any of these mixtures - they will work differently with different kinds of flowers!

One:
2 c. Sprite or 7-Up – not diet! (Note: It’s an acid lemon –lime brand with sugar!)
1/2 tsp. chlorine bleach
2 c. warm water

Two:
2 tbsp. lemon juice
1 tbsp. sugar
1/2 tsp chlorine bleach
1 qt. water

Three:
2 tbs. vinegar
1 tbs. sugar
1/2 tsp. chlorine bleach
1 qt. water

Christmas cactus bud drop
Q: My gorgeous, but fussy Christmas cactus finally decided to bloom – and I think it’s going to be beautiful! It’s loaded with buds – so I moved it to a place of honor in the dining room where it could be enjoyed in all its beauty. About three days after I moved the plant, I was horrified to see most all of the buds began to drop off the plant.
I was careful moving the plant - and the plant is getting about the same amount of light as it had been getting at the window – and the temperature is about the same, normal room temperature and so is my watering.
What could ever have made it drop? I’m so disappointed.

A: I hate to tell you, but yours is a common complaint. Everyone wants to display a beautifully blooming plant. When a budded Christmas cactus is moved from window to window, the buds turn toward the new light source. Leave them alone – or be very careful to notice if the light is coming from the back of the plant or the front – then duplicate the light angle.
You might be able to save to buds if you quickly return the plant to its original window spot and face it the way it was growing….otherwise, you’ll have to wait till next year’s buds. Sorry ‘bout that!

This week’s dirt…………………………………………………………
First aid for holiday plants-
Do the holiday plants, poinsettias and other gift plants, look sick? Are the leaves beginning to turn yellow, particularly near the bottom of the plant? Begin first aid immediately!
Hopefully, when you brought the plants home you didn’t allow them to get chilled!
Check the room temperature: Is the plant near a drafty window or door where it gets blasted by cold air? Or is it too near a heat source where it gets cooked? Is the fragile foliage touching the icy glass window? Then move it!
Take the foil wrapping off of gift plants and check for excess moisture – foil holds water and plants can easily rot if not drained. Water plants but don’t drown them – never let them stand in water for more than an hour or two. And try to increase the humidity in your dry house - everyone will benefit.
Is the plant getting enough light? Lots of filtered light is needed for blooming plants, but not direct sunlight.
Groom the plant, carefully removing dead or dying flowers and foliage.
With proper care, your holiday plants should stay beautiful for several weeks!