Half baked

Friends, I’m hiding indoors until this heat wave passes.

 
I have much to do in the garden, but it will have to wait. It hasn’t rained in weeks, and the ground is cracked open wide. I miss the summers of my childhood, when it seldom reached 90 degrees and almost every evening, it seemed, brought a soothing, cooling thunderstorm. Lately I’ve been catching the dish-rinsing water in a pan and running outside to relieve the container plants from their exhausted state.
Since I remain indoors, my patio umbrella shades the tomatoes and squash from the midday sun. Providing some shade can help your vegetables struggle through the hottest days and last longer into the season, but keep making succession sowings and keep those plants well mulched and watered.

Talk to you soon, my friends. I need a frosty beverage.

The waiting is the hardest part: Hardening off seedlings

I have three weeks to go until our average last frost date.

coldframe full

I did really well this winter, getting seeds sown and potting things on. Now, I’ve got to hang on until the tender things are safe to plant. The cold frame is jammed full.

Hardening off seedlings, though, is too important a process to skip. I skipped it all the time until I built my cold frame–mostly because I didn’t want to spend half the morning bringing trays of plants in and out of the house–and my plants performed correspondingly poorly.

Hardening off is a process of gradually exposing seedlings and tender plants to larger temperature variations and stronger light levels than they experience indoors. The process produces slower, sturdier, more resilient growth, preparing plants for life in the open garden. Without a cold frame, gardeners place plants in a sheltered location outside–maybe in a shaded site, close to the warmth of the house–for a short period of time, lengthening the exposure to outside conditions every few days.

Using a cold frame–basically a tiny greenhouse–makes the process far less tedious. It’s not quite a matter of set-it-and-forget-it, but it frees up lots of the time and space other parts of life demand. My cold frame, which I constructed myself from recycled materials for about $30, faces south and backs up to my house. I start hardening off my seedlings in mid-February, when we begin to see a few 50-degree (10C) days. I start with the hardy perennials, then move in the hardy annuals. Tender plants come last. Space permitting, I sow vegetable seeds in flats directly in the cold frame.

During the first few days in the frame, I place plants on its south side so they sit in slight shadow from the frame’s front wall. They gradually move towards the back as more plants come in. On unusually warm days, I vent the cold frame by propping open the glass doors, made of discarded windows. This keeps the temperatures inside from getting too hot–such fragile plants can quickly dehydrate and die if the temperatures climb too high. Sometimes I’ll prop open the windows entirely, but cover the opening with a bit of horticultural fabric. This practice lets the light in but keeps hungry foraging birds and squirrels and early insect pests out.

coldframe full 2

The second quadrant of the cold frame.

We’re getting close enough to the last-frost date that I may move out some of the plants with the longest tenancy–particularly the perennials–into permanent locations. They’ve withstood some cold nights already, so a late frost won’t likely bother them.

Believe, gardeners! The digging season is nearly here.

 

 

 

Wintertime houseplant health

I’m not under 4 feet of snow at the moment, but that doesn’t mean I want to spend a lot of time in the garden right now. Nor should I: It’s terribly damp, and I will compact the soil where I walk and damage its structure where I dig. So to scratch the gardening itch, I turn to my houseplants.

houseplant-collection-copyI am a terrible houseplant gardener. I never do anything as regularly as I should: I don’t water, I don’t turn my plants. I hope mainly to keep them on life support for a few months until it’s safe to take them outside again.

Extension agencies from Universities of Nebraska, and Maryland recommend the following tips to ensure your houseplants thrive in the winter months:

1. Increase the humidity…

That dry, centrally heated air that dries out your skin, hair, and eyes parches your houseplants, too. The air inside your home may have as low as 10% humidity, but plants (and humans) desire humidity of around 40%. Use a humidifier, or set plants on trays of pebbles filled with water (make sure the pots aren’t sitting in water). If you can, keep your plants with high humidity needs in the bathroom, where they can benefit from your steamy shower.

 2. But don’t overwater.

Ferns like evenly moist soil, and succulents like it very dry. For most all other plants, wait to water until the soil is dry to the touch, down to the depth of your first knuckle. Don’t assume that your plant needs watering once a week. Most indoor gardeners overwater rather than underwater their plants. Letting the soil dry out between waterings cuts down on the prevalence of fungus gnats.

When you do water, allow the water to saturate the soil and run through the bottom of the pot. Better yet, set the pot in a shallow pan of water for a short time. The dry soil will wick water up until the plant has what it needs. You’ll know it’s time to take the pot out of the water when the top of the soil looks moist, or when the container stops emitting air bubbles. Never let the pot sit in water longer than necessary.

3. Skip the fertilizer.

Most plants need a period of rest or dormancy in the winter months, when they’re not actively growing. Feeding encourages growth and robs your plants of a chance to recharge and get ready for the growing season ahead. Save the fertilizer until spring.

4. Avoid temperature extremes.

Wide swings in temperature, such as a blast of cold air from an open door or a perpetually heated breeze from a vent, stress plants. Don’t forget that window glass can be quite cold. As you edge your plants to the window to grasp what light they can, be sure to keep the foliage from touching the glass.

5. Spin me right round.

An additional tip from garden blogger and houseplant guru Lisa Steinkopf,  is to give your plants a quarter-turn every time you water. You’ve observed plants growing towards their light source. Rotating the plant keeps it growing straight.

 

Cold frames

Welcome back, gardening friends! I hope you had a wonderful holiday season and a happy new year.

The deep freeze that has hit most of the eastern half of the United States has just found its way to me. Fortunately, over the long holiday break, I took advantage of some warmish weather to repair my cold frame, which took a bit of a beating during the recent home renovation.

A cold frame is a simple enclosure with a clear or translucent roof that is used to shelter plants from cold or otherwise inclement weather. It is similar to a greenhouse, only generally less grand, and specifically, unheated. It can sit low to the ground or even be dug into the ground. It can shelter pots or can be planted directly, depending on the user’s needs.

I built mine out of recycled materials three years ago. It is a simple wooden box, measuring 8 feet long by 3 feet wide, and slopes from 20 inches tall at the back to 15 inches in the front.cold frame

Because the area where it is located contains the main electricity line to the house, the box sits on the surface, atop of a thick layer of gravel. In a colder climate, I might dig the cold frame into the ground, but it seldom stays very cold here for long.

The frame windows are upcycled window sashes from the Habitat for Humanity ReStore.

pots of greens in the cold frameIn the past, I lined the perimeter of the frames with foam weatherstripping, which does a good job of keeping out the cold air. However, it becomes brittle after a season and must be replaced annually.

The white-painted interior reflects light to the plants inside. The cold frame faces south, but tall trees to the southeast block some sun, even in the winter. (I’ll paint the outside to match the house when the weather warms up.) The cold frame does an excellent job of sheltering  tender plants, like my salad bowl garden. It also keeps my worm composting bin frost-free, allowing the worms to continue their good work, albeit more slowly, in the coldest months.

broken window panes on my cold frame

One of the window sashes was damaged during the renovation and must be replaced. I have been slow to fix it because its sorry state has spared me from having to vent the box during the warmest part of the day. I cannot replace the window today, but with overnight temperatures expected in the single digits Fahrenheit (that’s very cold for here), I need to make some arrangements to compensate for the heat loss the broken window allows.

First, I’ve crowded my plants together tightly in the section furthest away from the broken window. Reducing the gaps where frigid air can circulate will help the plants survive. I’m moving a few of my winter sowing seed pans and cuttings into the frame as extra insurance, though that does go against the philosophy of winter sowing.

crowded pots in the cold frame

Next, I took a few old shopping bags from my shed, filled them with dry leaves, and tied the handles closed. I tucked these in amongst the plants inside the frame. These will act as makeshift insulation batts, sheltering the plants from any drafts.

Third, I cut a double-thickness section of 3.5-mil translucent plastic sheeting to fit the window frame and stapled it into place, to help compensate for the broken panes of glass.

A double thickness of 3.5 mil plastic sheeting compensates for the broken glass panes.

Finally, below the window sashes but above the plants, I added a layer of that same 3.5 mil plastic sheeting and some cardboard before it goes to the recycling. This should stop most of the cold from penetrating the broken window.

cold frame put to bed

I know my northern neighbors are coping with much worse weather, and my thoughts are with you all. Stay warm and safe!

O water, where art thou?

A brief tutorial on water gardening for the novice:

Do: Add plants to your water garden.

Don’t: Forget to prune them occasionally.

runaway pond plants

Do: Use bricks to support planted baskets.

Don’t: Forget to prune, such that the roots envelop the bricks and make the plants very hard to remove from the pond.

bricks rescued from water iris roots

Those brick fragments are enjoying their first taste of freedom after spending at least a year in captivity of vigorous iris roots.

Do: Plant a variety of species.

Don’t: (ahem.) Let them grow together. They’re really hard to separate. But if you forget,

Do: Keep a sturdy garden knife around. Or a chainsaw.

DSC_0003

Do: Add fish to the garden to control mosquito larvae.

Don’t: Ask to see what happened to the fish in this garden. Basically, the plant roots grew together, creating an impenetrable mat. The water above the mat evaporated in three weeks of dry fall weather, and he couldn’t break through to the shallow water beneath the plants.

He was worth every penny of the dime I paid for him, though. He lived for two, or maybe three years. He now sleeps with the anemones. I feel terrible.

Do: Try again.

Azalea chlorosis

Or, Why Are My Azalea Leaves Turning Yellow?

Most of the subjects of the Great Azalea Migration have settled in well. I pruned them directly after this year’s flowering to give them more shape. Waiting too long to prune risks cutting off next year’s flowers.

This one, however, is showing signs of displeasure.

chlorotic azaleas yellow leaes green veins

Notice how the leaves are more yellow than green, but the veins remain dark green? This is a sign of chlorosis, a condition in which the leaves don’t produce adequate chlorophyll. The source of the problem lies in the soil’s pH; if the pH is not appropriate for the plant, that is, if the pH is too low (acid) or too high (alkaline), the plant’s roots cannot take up the nutrients (in this case, iron) in the soil. The solution to such a problem, therefore, is not to dump fertilizer on the plant, but to test the soil’s pH to confirm the diagnosis and then adjust it accordingly.

Azalea Growing Conditions

Azaleas like acid soil, typically in the pH range of 4.5 to 6. My soil falls within this range naturally. But it is possible that when this shrub was transplanted, some lime got mixed into the compost by accident; or it might have happened when I planted some smaller perennials at its base. Azaleas also want a shady location, or one that receives some morning sun. The light exposure is not the problem here.

This condition is interesting to me, because as you can see the older foliage is perfectly green. I would have thought the problem would be more evenly distributed on the plant.

So I will try to get a soil test for this patch of ground in the coming week or so. And if you are very good, I will show you the results and the remedy.